Merge branch 'gawk-4.2-stable' into feature/gnulib-regex

9 files changed, 2004 insertions, 518 deletions

diff --git a/ChangeLog b/ChangeLog
index 2a3f28f7..8c14e914 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2018-08-17         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* config.sub: Updated from GNULIB.
+
 2018-08-10         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* config.guess, config.sub: Updated from GNULIB.
diff --git a/config.sub b/config.sub
index 97d38aa6..6e8fa655 100755
--- a/config.sub
+++ b/config.sub
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2018 Free Software Foundation, Inc.
 
-timestamp='2018-07-25'
+timestamp='2018-08-13'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -149,29 +149,39 @@ case $1 in
 		esac
 		;;
 	*-*)
-		# Second component is usually, but not always the OS
-		case $field2 in
-			# Prevent following clause from handling this valid os
-			sun*os*)
-				basic_machine=$field1
-				os=$field2
-				;;
-			# Manufacturers
-			dec* | mips* | sequent* | encore* | pc532* | sgi* | sony* \
-			| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
-			| unicom* | ibm* | next | hp | isi* | apollo | altos* \
-			| convergent* | ncr* | news | 32* | 3600* | 3100* | hitachi* \
-			| c[123]* | convex* | sun | crds | omron* | dg | ultra | tti* \
-			| harris | dolphin | highlevel | gould | cbm | ns | masscomp \
-			| apple | axis | knuth | cray | microblaze* \
-			| sim | cisco | oki | wec | wrs | winbond)
-				basic_machine=$field1-$field2
+		# A lone config we happen to match not fitting any patern
+		case $field1-$field2 in
+			decstation-3100)
+				basic_machine=mips-dec
 				os=
 				;;
-			*)
-				basic_machine=$field1
-				os=$field2
-				;;
+			*-*)
+				# Second component is usually, but not always the OS
+				case $field2 in
+					# Prevent following clause from handling this valid os
+					sun*os*)
+						basic_machine=$field1
+						os=$field2
+						;;
+					# Manufacturers
+					dec* | mips* | sequent* | encore* | pc533* | sgi* | sony* \
+					| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
+					| unicom* | ibm* | next | hp | isi* | apollo | altos* \
+					| convergent* | ncr* | news | 32* | 3600* | 3100* \
+					| hitachi* | c[123]* | convex* | sun | crds | omron* | dg \
+					| ultra | tti* | harris | dolphin | highlevel | gould \
+					| cbm | ns | masscomp | apple | axis | knuth | cray \
+					| microblaze* | sim | cisco \
+					| oki | wec | wrs | winbond)
+						basic_machine=$field1-$field2
+						os=
+						;;
+					*)
+						basic_machine=$field1
+						os=$field2
+						;;
+				esac
+			;;
 		esac
 		;;
 	*)
@@ -190,6 +200,14 @@ case $1 in
 				basic_machine=m68010-adobe
 				os=scout
 				;;
+			alliant)
+				basic_machine=fx80-alliant
+				os=
+				;;
+			altos | altos3068)
+				basic_machine=m68k-altos
+				os=
+				;;
 			am29k)
 				basic_machine=a29k-none
 				os=bsd
@@ -198,6 +216,10 @@ case $1 in
 				basic_machine=580-amdahl
 				os=sysv
 				;;
+			amiga)
+				basic_machine=m68k-unknown
+				os=
+				;;
 			amigaos | amigados)
 				basic_machine=m68k-unknown
 				os=amigaos
@@ -234,13 +256,41 @@ case $1 in
 				basic_machine=arm-unknown
 				os=cegcc
 				;;
+			convex-c1)
+				basic_machine=c1-convex
+				os=bsd
+				;;
+			convex-c2)
+				basic_machine=c2-convex
+				os=bsd
+				;;
+			convex-c32)
+				basic_machine=c32-convex
+				os=bsd
+				;;
+			convex-c34)
+				basic_machine=c34-convex
+				os=bsd
+				;;
+			convex-c38)
+				basic_machine=c38-convex
+				os=bsd
+				;;
 			cray)
 				basic_machine=j90-cray
 				os=unicos
 				;;
-			craynv)
-				basic_machine=craynv-cray
-				os=unicosmp
+			crds | unos)
+				basic_machine=m68k-crds
+				os=
+				;;
+			da30)
+				basic_machine=m68k-da30
+				os=
+				;;
+			decstation | pmax | pmin | dec3100 | decstatn)
+				basic_machine=mips-dec
+				os=
 				;;
 			delta88)
 				basic_machine=m88k-motorola
@@ -286,6 +336,9 @@ case $1 in
 				basic_machine=m88k-harris
 				os=sysv3
 				;;
+			hp300)
+				basic_machine=m68k-hp
+				;;
 			hp300bsd)
 				basic_machine=m68k-hp
 				os=bsd
@@ -454,14 +507,26 @@ case $1 in
 				basic_machine=mips-sei
 				os=seiux
 				;;
+			sequent)
+				basic_machine=i386-sequent
+				os=
+				;;
 			sps7)
 				basic_machine=m68k-bull
 				os=sysv2
 				;;
+			st2000)
+				basic_machine=m68k-tandem
+				os=
+				;;
 			stratus)
 				basic_machine=i860-stratus
 				os=sysv4
 				;;
+			sun2)
+				basic_machine=m68000-sun
+				os=
+				;;
 			sun2os3)
 				basic_machine=m68000-sun
 				os=sunos3
@@ -470,6 +535,10 @@ case $1 in
 				basic_machine=m68000-sun
 				os=sunos4
 				;;
+			sun3)
+				basic_machine=m68k-sun
+				os=
+				;;
 			sun3os3)
 				basic_machine=m68k-sun
 				os=sunos3
@@ -478,6 +547,10 @@ case $1 in
 				basic_machine=m68k-sun
 				os=sunos4
 				;;
+			sun4)
+				basic_machine=sparc-sun
+				os=
+				;;
 			sun4os3)
 				basic_machine=sparc-sun
 				os=sunos3
@@ -490,6 +563,10 @@ case $1 in
 				basic_machine=sparc-sun
 				os=solaris2
 				;;
+			sun386 | sun386i | roadrunner)
+				basic_machine=i386-sun
+				os=
+				;;
 			sv1)
 				basic_machine=sv1-cray
 				os=unicos
@@ -564,6 +641,64 @@ esac
 
 # Decode aliases for certain CPU-COMPANY combinations.
 case $basic_machine in
+	# Here we handle the default manufacturer of certain CPU types.  It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	craynv)
+		basic_machine=craynv-cray
+		os=${os:-unicosmp}
+		;;
+	fx80)
+		basic_machine=fx80-alliant
+		;;
+	w89k)
+		basic_machine=hppa1.1-winbond
+		;;
+	op50n)
+		basic_machine=hppa1.1-oki
+		;;
+	op60c)
+		basic_machine=hppa1.1-oki
+		;;
+	romp)
+		basic_machine=romp-ibm
+		;;
+	mmix)
+		basic_machine=mmix-knuth
+		;;
+	rs6000)
+		basic_machine=rs6000-ibm
+		;;
+	vax)
+		basic_machine=vax-dec
+		;;
+	pdp11)
+		basic_machine=pdp11-dec
+		;;
+	we32k)
+		basic_machine=we32k-att
+		;;
+	cydra)
+		basic_machine=cydra-cydrome
+		;;
+	i370-ibm* | ibm*)
+		basic_machine=i370-ibm
+		;;
+	orion)
+		basic_machine=orion-highlevel
+		;;
+	orion105)
+		basic_machine=clipper-highlevel
+		;;
+	mac | mpw | mac-mpw)
+		basic_machine=m68k-apple
+		;;
+	pmac | pmac-mpw)
+		basic_machine=powerpc-apple
+		;;
+	xps | xps100)
+		basic_machine=xps100-honeywell
+		;;
+
 	# Recognize the basic CPU types without company name.
 	# Some are omitted here because they have special meanings below.
 	1750a | 580 \
@@ -592,6 +727,7 @@ case $basic_machine in
 	| le32 | le64 \
 	| lm32 \
 	| m32c | m32r | m32rle | m68000 | m68k | m88k \
+	| m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip \
 	| maxq | mb | microblaze | microblazeel | mcore | mep | metag \
 	| mips | mipsbe | mipseb | mipsel | mipsle \
 	| mips16 \
@@ -640,7 +776,7 @@ case $basic_machine in
 	| v850 | v850e | v850e1 | v850e2 | v850es | v850e2v3 \
 	| visium \
 	| wasm32 \
-	| x86 | xc16x | xstormy16 | xtensa \
+	| x86 | xc16x | xstormy16 | xgate | xtensa \
 	| z8k | z80)
 		basic_machine=$basic_machine-unknown
 		;;
@@ -656,11 +792,6 @@ case $basic_machine in
 	leon|leon[3-9])
 		basic_machine=sparc-$basic_machine
 		;;
-	m6811-* | m68hc11-* | m6812-* | m68hc12-* | m68hcs12x-* | nvptx-* | picochip-*)
-		;;
-	m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip)
-		basic_machine=$basic_machine-unknown
-		;;
 	m88110 | m680[12346]0 | m683?2 | m68360 | m5200 | v70 | w65)
 		;;
 	m9s12z | m68hcs12z | hcs12z | s12z)
@@ -675,11 +806,6 @@ case $basic_machine in
 	strongarm | thumb | xscale)
 		basic_machine=arm-unknown
 		;;
-	xgate)
-		basic_machine=$basic_machine-unknown
-		;;
-	xgate-*)
-		;;
 	xscaleeb)
 		basic_machine=armeb-unknown
 		;;
@@ -718,13 +844,14 @@ case $basic_machine in
 	| h8300-* | h8500-* \
 	| hppa-* | hppa1.[01]-* | hppa2.0-* | hppa2.0[nw]-* | hppa64-* \
 	| hexagon-* \
-	| i*86-* | i860-* | i960-* | ia16-* | ia64-* \
+	| i370-* | i*86-* | i860-* | i960-* | ia16-* | ia64-* \
 	| ip2k-* | iq2000-* \
 	| k1om-* \
 	| le32-* | le64-* \
 	| lm32-* \
 	| m32c-* | m32r-* | m32rle-* \
 	| m5200-* | m68000-* | m680[012346]0-* | m68360-* | m683?2-* | m68k-* | v70-* | w65-* \
+	| m6811-* | m68hc11-* | m6812-* | m68hc12-* | m68hcs12x-* | nvptx-* | picochip-* \
 	| m88110-* | m88k-* | maxq-* | mb-* | mcore-* | mep-* | metag-* \
 	| microblaze-* | microblazeel-* \
 	| mips-* | mipsbe-* | mipseb-* | mipsel-* | mipsle-* \
@@ -783,7 +910,7 @@ case $basic_machine in
 	| visium-* \
 	| wasm32-* \
 	| we32k-* \
-	| x86-* | x86_64-* | xc16x-* | xps100-* \
+	| x86-* | x86_64-* | xc16x-* | xgate-* | xps100-* \
 	| xstormy16-* | xtensa*-* \
 	| ymp-* \
 	| z8k-* | z80-*)
@@ -800,21 +927,12 @@ case $basic_machine in
 	3b*)
 		basic_machine=we32k-att
 		;;
-	alliant | fx80)
-		basic_machine=fx80-alliant
-		;;
-	altos | altos3068)
-		basic_machine=m68k-altos
-		;;
 	amd64)
 		basic_machine=x86_64-pc
 		;;
 	amd64-*)
 		basic_machine=x86_64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		;;
-	amiga | amiga-*)
-		basic_machine=m68k-unknown
-		;;
 	blackfin-*)
 		basic_machine=bfin-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		os=linux
@@ -836,33 +954,10 @@ case $basic_machine in
 		basic_machine=c90-cray
 		os=${os:-unicos}
 		;;
-	convex-c1)
-		basic_machine=c1-convex
-		os=bsd
-		;;
-	convex-c2)
-		basic_machine=c2-convex
-		os=bsd
-		;;
-	convex-c32)
-		basic_machine=c32-convex
-		os=bsd
-		;;
-	convex-c34)
-		basic_machine=c34-convex
-		os=bsd
-		;;
-	convex-c38)
-		basic_machine=c38-convex
-		os=bsd
-		;;
 	cr16 | cr16-*)
 		basic_machine=cr16-unknown
 		os=${os:-elf}
 		;;
-	crds | unos)
-		basic_machine=m68k-crds
-		;;
 	crisv32 | crisv32-* | etraxfs*)
 		basic_machine=crisv32-axis
 		;;
@@ -873,12 +968,6 @@ case $basic_machine in
 		basic_machine=crx-unknown
 		os=${os:-elf}
 		;;
-	da30 | da30-*)
-		basic_machine=m68k-da30
-		;;
-	decstation | decstation-3100 | pmax | pmax-* | pmin | dec3100 | decstatn)
-		basic_machine=mips-dec
-		;;
 	decsystem10* | dec10*)
 		basic_machine=pdp10-dec
 		os=tops10
@@ -924,9 +1013,6 @@ case $basic_machine in
 		basic_machine=hppa1.1-hitachi
 		os=hiuxwe2
 		;;
-	hp300-*)
-		basic_machine=m68k-hp
-		;;
 	hp3k9[0-9][0-9] | hp9[0-9][0-9])
 		basic_machine=hppa1.0-hp
 		;;
@@ -956,9 +1042,6 @@ case $basic_machine in
 	hp9k8[0-9][0-9] | hp8[0-9][0-9])
 		basic_machine=hppa1.0-hp
 		;;
-	i370-ibm* | ibm*)
-		basic_machine=i370-ibm
-		;;
 	i*86v32)
 		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
 		os=sysv32
@@ -1155,9 +1238,6 @@ case $basic_machine in
 		basic_machine=mipsisa32-sde
 		os=${os:-elf}
 		;;
-	sequent)
-		basic_machine=i386-sequent
-		;;
 	sh5el)
 		basic_machine=sh5le-unknown
 		;;
@@ -1171,24 +1251,9 @@ case $basic_machine in
 	spur)
 		basic_machine=spur-unknown
 		;;
-	st2000)
-		basic_machine=m68k-tandem
-		;;
 	strongarm-* | thumb-*)
 		basic_machine=arm-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		;;
-	sun2)
-		basic_machine=m68000-sun
-		;;
-	sun3 | sun3-*)
-		basic_machine=m68k-sun
-		;;
-	sun4)
-		basic_machine=sparc-sun
-		;;
-	sun386 | sun386i | roadrunner)
-		basic_machine=i386-sun
-		;;
 	tile*-*)
 		;;
 	tile*)
@@ -1218,9 +1283,6 @@ case $basic_machine in
 	x64)
 		basic_machine=x86_64-pc
 		;;
-	xps | xps100)
-		basic_machine=xps100-honeywell
-		;;
 	xscale-* | xscalee[bl]-*)
 		basic_machine=`echo "$basic_machine" | sed 's/^xscale/arm/'`
 		;;
@@ -1228,50 +1290,6 @@ case $basic_machine in
 		basic_machine=none-none
 		;;
 
-# Here we handle the default manufacturer of certain CPU types.  It is in
-# some cases the only manufacturer, in others, it is the most popular.
-	w89k)
-		basic_machine=hppa1.1-winbond
-		;;
-	op50n)
-		basic_machine=hppa1.1-oki
-		;;
-	op60c)
-		basic_machine=hppa1.1-oki
-		;;
-	romp)
-		basic_machine=romp-ibm
-		;;
-	mmix)
-		basic_machine=mmix-knuth
-		;;
-	rs6000)
-		basic_machine=rs6000-ibm
-		;;
-	vax)
-		basic_machine=vax-dec
-		;;
-	pdp11)
-		basic_machine=pdp11-dec
-		;;
-	we32k)
-		basic_machine=we32k-att
-		;;
-	cydra)
-		basic_machine=cydra-cydrome
-		;;
-	orion)
-		basic_machine=orion-highlevel
-		;;
-	orion105)
-		basic_machine=clipper-highlevel
-		;;
-	mac | mpw | mac-mpw)
-		basic_machine=m68k-apple
-		;;
-	pmac | pmac-mpw)
-		basic_machine=powerpc-apple
-		;;
 	*)
 		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
 		exit 1
diff --git a/extension/build-aux/ChangeLog b/extension/build-aux/ChangeLog
index 3b662dd3..1e8806d5 100644
--- a/extension/build-aux/ChangeLog
+++ b/extension/build-aux/ChangeLog
@@ -1,3 +1,7 @@
+2018-08-17         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* config.sub: Updated from GNULIB.
+
 2018-08-10         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* config.guess, config.sub: Updated from GNULIB.
diff --git a/extension/build-aux/config.sub b/extension/build-aux/config.sub
index 97d38aa6..6e8fa655 100755
--- a/extension/build-aux/config.sub
+++ b/extension/build-aux/config.sub
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2018 Free Software Foundation, Inc.
 
-timestamp='2018-07-25'
+timestamp='2018-08-13'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -149,29 +149,39 @@ case $1 in
 		esac
 		;;
 	*-*)
-		# Second component is usually, but not always the OS
-		case $field2 in
-			# Prevent following clause from handling this valid os
-			sun*os*)
-				basic_machine=$field1
-				os=$field2
-				;;
-			# Manufacturers
-			dec* | mips* | sequent* | encore* | pc532* | sgi* | sony* \
-			| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
-			| unicom* | ibm* | next | hp | isi* | apollo | altos* \
-			| convergent* | ncr* | news | 32* | 3600* | 3100* | hitachi* \
-			| c[123]* | convex* | sun | crds | omron* | dg | ultra | tti* \
-			| harris | dolphin | highlevel | gould | cbm | ns | masscomp \
-			| apple | axis | knuth | cray | microblaze* \
-			| sim | cisco | oki | wec | wrs | winbond)
-				basic_machine=$field1-$field2
+		# A lone config we happen to match not fitting any patern
+		case $field1-$field2 in
+			decstation-3100)
+				basic_machine=mips-dec
 				os=
 				;;
-			*)
-				basic_machine=$field1
-				os=$field2
-				;;
+			*-*)
+				# Second component is usually, but not always the OS
+				case $field2 in
+					# Prevent following clause from handling this valid os
+					sun*os*)
+						basic_machine=$field1
+						os=$field2
+						;;
+					# Manufacturers
+					dec* | mips* | sequent* | encore* | pc533* | sgi* | sony* \
+					| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
+					| unicom* | ibm* | next | hp | isi* | apollo | altos* \
+					| convergent* | ncr* | news | 32* | 3600* | 3100* \
+					| hitachi* | c[123]* | convex* | sun | crds | omron* | dg \
+					| ultra | tti* | harris | dolphin | highlevel | gould \
+					| cbm | ns | masscomp | apple | axis | knuth | cray \
+					| microblaze* | sim | cisco \
+					| oki | wec | wrs | winbond)
+						basic_machine=$field1-$field2
+						os=
+						;;
+					*)
+						basic_machine=$field1
+						os=$field2
+						;;
+				esac
+			;;
 		esac
 		;;
 	*)
@@ -190,6 +200,14 @@ case $1 in
 				basic_machine=m68010-adobe
 				os=scout
 				;;
+			alliant)
+				basic_machine=fx80-alliant
+				os=
+				;;
+			altos | altos3068)
+				basic_machine=m68k-altos
+				os=
+				;;
 			am29k)
 				basic_machine=a29k-none
 				os=bsd
@@ -198,6 +216,10 @@ case $1 in
 				basic_machine=580-amdahl
 				os=sysv
 				;;
+			amiga)
+				basic_machine=m68k-unknown
+				os=
+				;;
 			amigaos | amigados)
 				basic_machine=m68k-unknown
 				os=amigaos
@@ -234,13 +256,41 @@ case $1 in
 				basic_machine=arm-unknown
 				os=cegcc
 				;;
+			convex-c1)
+				basic_machine=c1-convex
+				os=bsd
+				;;
+			convex-c2)
+				basic_machine=c2-convex
+				os=bsd
+				;;
+			convex-c32)
+				basic_machine=c32-convex
+				os=bsd
+				;;
+			convex-c34)
+				basic_machine=c34-convex
+				os=bsd
+				;;
+			convex-c38)
+				basic_machine=c38-convex
+				os=bsd
+				;;
 			cray)
 				basic_machine=j90-cray
 				os=unicos
 				;;
-			craynv)
-				basic_machine=craynv-cray
-				os=unicosmp
+			crds | unos)
+				basic_machine=m68k-crds
+				os=
+				;;
+			da30)
+				basic_machine=m68k-da30
+				os=
+				;;
+			decstation | pmax | pmin | dec3100 | decstatn)
+				basic_machine=mips-dec
+				os=
 				;;
 			delta88)
 				basic_machine=m88k-motorola
@@ -286,6 +336,9 @@ case $1 in
 				basic_machine=m88k-harris
 				os=sysv3
 				;;
+			hp300)
+				basic_machine=m68k-hp
+				;;
 			hp300bsd)
 				basic_machine=m68k-hp
 				os=bsd
@@ -454,14 +507,26 @@ case $1 in
 				basic_machine=mips-sei
 				os=seiux
 				;;
+			sequent)
+				basic_machine=i386-sequent
+				os=
+				;;
 			sps7)
 				basic_machine=m68k-bull
 				os=sysv2
 				;;
+			st2000)
+				basic_machine=m68k-tandem
+				os=
+				;;
 			stratus)
 				basic_machine=i860-stratus
 				os=sysv4
 				;;
+			sun2)
+				basic_machine=m68000-sun
+				os=
+				;;
 			sun2os3)
 				basic_machine=m68000-sun
 				os=sunos3
@@ -470,6 +535,10 @@ case $1 in
 				basic_machine=m68000-sun
 				os=sunos4
 				;;
+			sun3)
+				basic_machine=m68k-sun
+				os=
+				;;
 			sun3os3)
 				basic_machine=m68k-sun
 				os=sunos3
@@ -478,6 +547,10 @@ case $1 in
 				basic_machine=m68k-sun
 				os=sunos4
 				;;
+			sun4)
+				basic_machine=sparc-sun
+				os=
+				;;
 			sun4os3)
 				basic_machine=sparc-sun
 				os=sunos3
@@ -490,6 +563,10 @@ case $1 in
 				basic_machine=sparc-sun
 				os=solaris2
 				;;
+			sun386 | sun386i | roadrunner)
+				basic_machine=i386-sun
+				os=
+				;;
 			sv1)
 				basic_machine=sv1-cray
 				os=unicos
@@ -564,6 +641,64 @@ esac
 
 # Decode aliases for certain CPU-COMPANY combinations.
 case $basic_machine in
+	# Here we handle the default manufacturer of certain CPU types.  It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	craynv)
+		basic_machine=craynv-cray
+		os=${os:-unicosmp}
+		;;
+	fx80)
+		basic_machine=fx80-alliant
+		;;
+	w89k)
+		basic_machine=hppa1.1-winbond
+		;;
+	op50n)
+		basic_machine=hppa1.1-oki
+		;;
+	op60c)
+		basic_machine=hppa1.1-oki
+		;;
+	romp)
+		basic_machine=romp-ibm
+		;;
+	mmix)
+		basic_machine=mmix-knuth
+		;;
+	rs6000)
+		basic_machine=rs6000-ibm
+		;;
+	vax)
+		basic_machine=vax-dec
+		;;
+	pdp11)
+		basic_machine=pdp11-dec
+		;;
+	we32k)
+		basic_machine=we32k-att
+		;;
+	cydra)
+		basic_machine=cydra-cydrome
+		;;
+	i370-ibm* | ibm*)
+		basic_machine=i370-ibm
+		;;
+	orion)
+		basic_machine=orion-highlevel
+		;;
+	orion105)
+		basic_machine=clipper-highlevel
+		;;
+	mac | mpw | mac-mpw)
+		basic_machine=m68k-apple
+		;;
+	pmac | pmac-mpw)
+		basic_machine=powerpc-apple
+		;;
+	xps | xps100)
+		basic_machine=xps100-honeywell
+		;;
+
 	# Recognize the basic CPU types without company name.
 	# Some are omitted here because they have special meanings below.
 	1750a | 580 \
@@ -592,6 +727,7 @@ case $basic_machine in
 	| le32 | le64 \
 	| lm32 \
 	| m32c | m32r | m32rle | m68000 | m68k | m88k \
+	| m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip \
 	| maxq | mb | microblaze | microblazeel | mcore | mep | metag \
 	| mips | mipsbe | mipseb | mipsel | mipsle \
 	| mips16 \
@@ -640,7 +776,7 @@ case $basic_machine in
 	| v850 | v850e | v850e1 | v850e2 | v850es | v850e2v3 \
 	| visium \
 	| wasm32 \
-	| x86 | xc16x | xstormy16 | xtensa \
+	| x86 | xc16x | xstormy16 | xgate | xtensa \
 	| z8k | z80)
 		basic_machine=$basic_machine-unknown
 		;;
@@ -656,11 +792,6 @@ case $basic_machine in
 	leon|leon[3-9])
 		basic_machine=sparc-$basic_machine
 		;;
-	m6811-* | m68hc11-* | m6812-* | m68hc12-* | m68hcs12x-* | nvptx-* | picochip-*)
-		;;
-	m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip)
-		basic_machine=$basic_machine-unknown
-		;;
 	m88110 | m680[12346]0 | m683?2 | m68360 | m5200 | v70 | w65)
 		;;
 	m9s12z | m68hcs12z | hcs12z | s12z)
@@ -675,11 +806,6 @@ case $basic_machine in
 	strongarm | thumb | xscale)
 		basic_machine=arm-unknown
 		;;
-	xgate)
-		basic_machine=$basic_machine-unknown
-		;;
-	xgate-*)
-		;;
 	xscaleeb)
 		basic_machine=armeb-unknown
 		;;
@@ -718,13 +844,14 @@ case $basic_machine in
 	| h8300-* | h8500-* \
 	| hppa-* | hppa1.[01]-* | hppa2.0-* | hppa2.0[nw]-* | hppa64-* \
 	| hexagon-* \
-	| i*86-* | i860-* | i960-* | ia16-* | ia64-* \
+	| i370-* | i*86-* | i860-* | i960-* | ia16-* | ia64-* \
 	| ip2k-* | iq2000-* \
 	| k1om-* \
 	| le32-* | le64-* \
 	| lm32-* \
 	| m32c-* | m32r-* | m32rle-* \
 	| m5200-* | m68000-* | m680[012346]0-* | m68360-* | m683?2-* | m68k-* | v70-* | w65-* \
+	| m6811-* | m68hc11-* | m6812-* | m68hc12-* | m68hcs12x-* | nvptx-* | picochip-* \
 	| m88110-* | m88k-* | maxq-* | mb-* | mcore-* | mep-* | metag-* \
 	| microblaze-* | microblazeel-* \
 	| mips-* | mipsbe-* | mipseb-* | mipsel-* | mipsle-* \
@@ -783,7 +910,7 @@ case $basic_machine in
 	| visium-* \
 	| wasm32-* \
 	| we32k-* \
-	| x86-* | x86_64-* | xc16x-* | xps100-* \
+	| x86-* | x86_64-* | xc16x-* | xgate-* | xps100-* \
 	| xstormy16-* | xtensa*-* \
 	| ymp-* \
 	| z8k-* | z80-*)
@@ -800,21 +927,12 @@ case $basic_machine in
 	3b*)
 		basic_machine=we32k-att
 		;;
-	alliant | fx80)
-		basic_machine=fx80-alliant
-		;;
-	altos | altos3068)
-		basic_machine=m68k-altos
-		;;
 	amd64)
 		basic_machine=x86_64-pc
 		;;
 	amd64-*)
 		basic_machine=x86_64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		;;
-	amiga | amiga-*)
-		basic_machine=m68k-unknown
-		;;
 	blackfin-*)
 		basic_machine=bfin-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		os=linux
@@ -836,33 +954,10 @@ case $basic_machine in
 		basic_machine=c90-cray
 		os=${os:-unicos}
 		;;
-	convex-c1)
-		basic_machine=c1-convex
-		os=bsd
-		;;
-	convex-c2)
-		basic_machine=c2-convex
-		os=bsd
-		;;
-	convex-c32)
-		basic_machine=c32-convex
-		os=bsd
-		;;
-	convex-c34)
-		basic_machine=c34-convex
-		os=bsd
-		;;
-	convex-c38)
-		basic_machine=c38-convex
-		os=bsd
-		;;
 	cr16 | cr16-*)
 		basic_machine=cr16-unknown
 		os=${os:-elf}
 		;;
-	crds | unos)
-		basic_machine=m68k-crds
-		;;
 	crisv32 | crisv32-* | etraxfs*)
 		basic_machine=crisv32-axis
 		;;
@@ -873,12 +968,6 @@ case $basic_machine in
 		basic_machine=crx-unknown
 		os=${os:-elf}
 		;;
-	da30 | da30-*)
-		basic_machine=m68k-da30
-		;;
-	decstation | decstation-3100 | pmax | pmax-* | pmin | dec3100 | decstatn)
-		basic_machine=mips-dec
-		;;
 	decsystem10* | dec10*)
 		basic_machine=pdp10-dec
 		os=tops10
@@ -924,9 +1013,6 @@ case $basic_machine in
 		basic_machine=hppa1.1-hitachi
 		os=hiuxwe2
 		;;
-	hp300-*)
-		basic_machine=m68k-hp
-		;;
 	hp3k9[0-9][0-9] | hp9[0-9][0-9])
 		basic_machine=hppa1.0-hp
 		;;
@@ -956,9 +1042,6 @@ case $basic_machine in
 	hp9k8[0-9][0-9] | hp8[0-9][0-9])
 		basic_machine=hppa1.0-hp
 		;;
-	i370-ibm* | ibm*)
-		basic_machine=i370-ibm
-		;;
 	i*86v32)
 		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
 		os=sysv32
@@ -1155,9 +1238,6 @@ case $basic_machine in
 		basic_machine=mipsisa32-sde
 		os=${os:-elf}
 		;;
-	sequent)
-		basic_machine=i386-sequent
-		;;
 	sh5el)
 		basic_machine=sh5le-unknown
 		;;
@@ -1171,24 +1251,9 @@ case $basic_machine in
 	spur)
 		basic_machine=spur-unknown
 		;;
-	st2000)
-		basic_machine=m68k-tandem
-		;;
 	strongarm-* | thumb-*)
 		basic_machine=arm-`echo "$basic_machine" | sed 's/^[^-]*-//'`
 		;;
-	sun2)
-		basic_machine=m68000-sun
-		;;
-	sun3 | sun3-*)
-		basic_machine=m68k-sun
-		;;
-	sun4)
-		basic_machine=sparc-sun
-		;;
-	sun386 | sun386i | roadrunner)
-		basic_machine=i386-sun
-		;;
 	tile*-*)
 		;;
 	tile*)
@@ -1218,9 +1283,6 @@ case $basic_machine in
 	x64)
 		basic_machine=x86_64-pc
 		;;
-	xps | xps100)
-		basic_machine=xps100-honeywell
-		;;
 	xscale-* | xscalee[bl]-*)
 		basic_machine=`echo "$basic_machine" | sed 's/^xscale/arm/'`
 		;;
@@ -1228,50 +1290,6 @@ case $basic_machine in
 		basic_machine=none-none
 		;;
 
-# Here we handle the default manufacturer of certain CPU types.  It is in
-# some cases the only manufacturer, in others, it is the most popular.
-	w89k)
-		basic_machine=hppa1.1-winbond
-		;;
-	op50n)
-		basic_machine=hppa1.1-oki
-		;;
-	op60c)
-		basic_machine=hppa1.1-oki
-		;;
-	romp)
-		basic_machine=romp-ibm
-		;;
-	mmix)
-		basic_machine=mmix-knuth
-		;;
-	rs6000)
-		basic_machine=rs6000-ibm
-		;;
-	vax)
-		basic_machine=vax-dec
-		;;
-	pdp11)
-		basic_machine=pdp11-dec
-		;;
-	we32k)
-		basic_machine=we32k-att
-		;;
-	cydra)
-		basic_machine=cydra-cydrome
-		;;
-	orion)
-		basic_machine=orion-highlevel
-		;;
-	orion105)
-		basic_machine=clipper-highlevel
-		;;
-	mac | mpw | mac-mpw)
-		basic_machine=m68k-apple
-		;;
-	pmac | pmac-mpw)
-		basic_machine=powerpc-apple
-		;;
 	*)
 		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
 		exit 1
diff --git a/missing_d/ChangeLog b/missing_d/ChangeLog
index a5838ccc..ea309c26 100644
--- a/missing_d/ChangeLog
+++ b/missing_d/ChangeLog
@@ -1,3 +1,9 @@
+2018-08-17         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* mktime.c: Updated from GNULIB.
+	* verify.h, intprops.h: Copied from supprt, for mktime.c
+	* mktime.c.old: Original version, just in case.
+
 2018-03-13         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* snprintf.c: Update copyright year.
diff --git a/missing_d/intprops.h b/missing_d/intprops.h
new file mode 100644
index 00000000..af456ff5
--- /dev/null
+++ b/missing_d/intprops.h
@@ -0,0 +1,453 @@
+/* intprops.h -- properties of integer types
+
+   Copyright (C) 2001-2018 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 2.1 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#ifndef _GL_INTPROPS_H
+#define _GL_INTPROPS_H
+
+#include <limits.h>
+
+/* Return a value with the common real type of E and V and the value of V.  */
+#define _GL_INT_CONVERT(e, v) (0 * (e) + (v))
+
+/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see
+   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00406.html>.  */
+#define _GL_INT_NEGATE_CONVERT(e, v) (0 * (e) - (v))
+
+/* The extra casts in the following macros work around compiler bugs,
+   e.g., in Cray C 5.0.3.0.  */
+
+/* True if the arithmetic type T is an integer type.  bool counts as
+   an integer.  */
+#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
+
+/* True if the real type T is signed.  */
+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+
+/* Return 1 if the real expression E, after promotion, has a
+   signed or floating type.  */
+#define EXPR_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0)
+
+
+/* Minimum and maximum values for integer types and expressions.  */
+
+/* The width in bits of the integer type or expression T.
+   Padding bits are not supported; this is checked at compile-time below.  */
+#define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
+
+/* The maximum and minimum values for the integer type T.  */
+#define TYPE_MINIMUM(t) ((t) ~ TYPE_MAXIMUM (t))
+#define TYPE_MAXIMUM(t)                                                 \
+  ((t) (! TYPE_SIGNED (t)                                               \
+        ? (t) -1                                                        \
+        : ((((t) 1 << (TYPE_WIDTH (t) - 2)) - 1) * 2 + 1)))
+
+/* The maximum and minimum values for the type of the expression E,
+   after integer promotion.  E should not have side effects.  */
+#define _GL_INT_MINIMUM(e)                                              \
+  (EXPR_SIGNED (e)                                                      \
+   ? ~ _GL_SIGNED_INT_MAXIMUM (e)                                       \
+   : _GL_INT_CONVERT (e, 0))
+#define _GL_INT_MAXIMUM(e)                                              \
+  (EXPR_SIGNED (e)                                                      \
+   ? _GL_SIGNED_INT_MAXIMUM (e)                                         \
+   : _GL_INT_NEGATE_CONVERT (e, 1))
+#define _GL_SIGNED_INT_MAXIMUM(e)                                       \
+  (((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH ((e) + 0) - 2)) - 1) * 2 + 1)
+
+/* Work around OpenVMS incompatibility with C99.  */
+#if !defined LLONG_MAX && defined __INT64_MAX
+# define LLONG_MAX __INT64_MAX
+# define LLONG_MIN __INT64_MIN
+#endif
+
+/* This include file assumes that signed types are two's complement without
+   padding bits; the above macros have undefined behavior otherwise.
+   If this is a problem for you, please let us know how to fix it for your host.
+   This assumption is tested by the intprops-tests module.  */
+
+/* Does the __typeof__ keyword work?  This could be done by
+   'configure', but for now it's easier to do it by hand.  */
+#if (2 <= __GNUC__ \
+     || (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
+     || (0x5110 <= __SUNPRO_C && !__STDC__))
+# define _GL_HAVE___TYPEOF__ 1
+#else
+# define _GL_HAVE___TYPEOF__ 0
+#endif
+
+/* Return 1 if the integer type or expression T might be signed.  Return 0
+   if it is definitely unsigned.  This macro does not evaluate its argument,
+   and expands to an integer constant expression.  */
+#if _GL_HAVE___TYPEOF__
+# define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t))
+#else
+# define _GL_SIGNED_TYPE_OR_EXPR(t) 1
+#endif
+
+/* Bound on length of the string representing an unsigned integer
+   value representable in B bits.  log10 (2.0) < 146/485.  The
+   smallest value of B where this bound is not tight is 2621.  */
+#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
+
+/* Bound on length of the string representing an integer type or expression T.
+   Subtract 1 for the sign bit if T is signed, and then add 1 more for
+   a minus sign if needed.
+
+   Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 0 when its argument is
+   signed, this macro may overestimate the true bound by one byte when
+   applied to unsigned types of size 2, 4, 16, ... bytes.  */
+#define INT_STRLEN_BOUND(t)                                     \
+  (INT_BITS_STRLEN_BOUND (TYPE_WIDTH (t) - _GL_SIGNED_TYPE_OR_EXPR (t)) \
+   + _GL_SIGNED_TYPE_OR_EXPR (t))
+
+/* Bound on buffer size needed to represent an integer type or expression T,
+   including the terminating null.  */
+#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
+
+
+/* Range overflow checks.
+
+   The INT_<op>_RANGE_OVERFLOW macros return 1 if the corresponding C
+   operators might not yield numerically correct answers due to
+   arithmetic overflow.  They do not rely on undefined or
+   implementation-defined behavior.  Their implementations are simple
+   and straightforward, but they are a bit harder to use than the
+   INT_<op>_OVERFLOW macros described below.
+
+   Example usage:
+
+     long int i = ...;
+     long int j = ...;
+     if (INT_MULTIPLY_RANGE_OVERFLOW (i, j, LONG_MIN, LONG_MAX))
+       printf ("multiply would overflow");
+     else
+       printf ("product is %ld", i * j);
+
+   Restrictions on *_RANGE_OVERFLOW macros:
+
+   These macros do not check for all possible numerical problems or
+   undefined or unspecified behavior: they do not check for division
+   by zero, for bad shift counts, or for shifting negative numbers.
+
+   These macros may evaluate their arguments zero or multiple times,
+   so the arguments should not have side effects.  The arithmetic
+   arguments (including the MIN and MAX arguments) must be of the same
+   integer type after the usual arithmetic conversions, and the type
+   must have minimum value MIN and maximum MAX.  Unsigned types should
+   use a zero MIN of the proper type.
+
+   These macros are tuned for constant MIN and MAX.  For commutative
+   operations such as A + B, they are also tuned for constant B.  */
+
+/* Return 1 if A + B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  */
+#define INT_ADD_RANGE_OVERFLOW(a, b, min, max)          \
+  ((b) < 0                                              \
+   ? (a) < (min) - (b)                                  \
+   : (max) - (b) < (a))
+
+/* Return 1 if A - B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  */
+#define INT_SUBTRACT_RANGE_OVERFLOW(a, b, min, max)     \
+  ((b) < 0                                              \
+   ? (max) + (b) < (a)                                  \
+   : (a) < (min) + (b))
+
+/* Return 1 if - A would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  */
+#define INT_NEGATE_RANGE_OVERFLOW(a, min, max)          \
+  ((min) < 0                                            \
+   ? (a) < - (max)                                      \
+   : 0 < (a))
+
+/* Return 1 if A * B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  Avoid && and || as they tickle
+   bugs in Sun C 5.11 2010/08/13 and other compilers; see
+   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00401.html>.  */
+#define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max)     \
+  ((b) < 0                                              \
+   ? ((a) < 0                                           \
+      ? (a) < (max) / (b)                               \
+      : (b) == -1                                       \
+      ? 0                                               \
+      : (min) / (b) < (a))                              \
+   : (b) == 0                                           \
+   ? 0                                                  \
+   : ((a) < 0                                           \
+      ? (a) < (min) / (b)                               \
+      : (max) / (b) < (a)))
+
+/* Return 1 if A / B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  Do not check for division by zero.  */
+#define INT_DIVIDE_RANGE_OVERFLOW(a, b, min, max)       \
+  ((min) < 0 && (b) == -1 && (a) < - (max))
+
+/* Return 1 if A % B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  Do not check for division by zero.
+   Mathematically, % should never overflow, but on x86-like hosts
+   INT_MIN % -1 traps, and the C standard permits this, so treat this
+   as an overflow too.  */
+#define INT_REMAINDER_RANGE_OVERFLOW(a, b, min, max)    \
+  INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max)
+
+/* Return 1 if A << B would overflow in [MIN,MAX] arithmetic.
+   See above for restrictions.  Here, MIN and MAX are for A only, and B need
+   not be of the same type as the other arguments.  The C standard says that
+   behavior is undefined for shifts unless 0 <= B < wordwidth, and that when
+   A is negative then A << B has undefined behavior and A >> B has
+   implementation-defined behavior, but do not check these other
+   restrictions.  */
+#define INT_LEFT_SHIFT_RANGE_OVERFLOW(a, b, min, max)   \
+  ((a) < 0                                              \
+   ? (a) < (min) >> (b)                                 \
+   : (max) >> (b) < (a))
+
+/* True if __builtin_add_overflow (A, B, P) works when P is non-null.  */
+#if 5 <= __GNUC__ && !defined __ICC
+# define _GL_HAS_BUILTIN_OVERFLOW 1
+#else
+# define _GL_HAS_BUILTIN_OVERFLOW 0
+#endif
+
+/* True if __builtin_add_overflow_p (A, B, C) works.  */
+#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
+
+/* The _GL*_OVERFLOW macros have the same restrictions as the
+   *_RANGE_OVERFLOW macros, except that they do not assume that operands
+   (e.g., A and B) have the same type as MIN and MAX.  Instead, they assume
+   that the result (e.g., A + B) has that type.  */
+#if _GL_HAS_BUILTIN_OVERFLOW_P
+# define _GL_ADD_OVERFLOW(a, b, min, max)                               \
+   __builtin_add_overflow_p (a, b, (__typeof__ ((a) + (b))) 0)
+# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                          \
+   __builtin_sub_overflow_p (a, b, (__typeof__ ((a) - (b))) 0)
+# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                          \
+   __builtin_mul_overflow_p (a, b, (__typeof__ ((a) * (b))) 0)
+#else
+# define _GL_ADD_OVERFLOW(a, b, min, max)                                \
+   ((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max)                  \
+    : (a) < 0 ? (b) <= (a) + (b)                                         \
+    : (b) < 0 ? (a) <= (a) + (b)                                         \
+    : (a) + (b) < (b))
+# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                           \
+   ((min) < 0 ? INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max)             \
+    : (a) < 0 ? 1                                                        \
+    : (b) < 0 ? (a) - (b) <= (a)                                         \
+    : (a) < (b))
+# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                           \
+   (((min) == 0 && (((a) < 0 && 0 < (b)) || ((b) < 0 && 0 < (a))))       \
+    || INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max))
+#endif
+#define _GL_DIVIDE_OVERFLOW(a, b, min, max)                             \
+  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
+   : (a) < 0 ? (b) <= (a) + (b) - 1                                     \
+   : (b) < 0 && (a) + (b) <= (a))
+#define _GL_REMAINDER_OVERFLOW(a, b, min, max)                          \
+  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
+   : (a) < 0 ? (a) % (b) != ((max) - (b) + 1) % (b)                     \
+   : (b) < 0 && ! _GL_UNSIGNED_NEG_MULTIPLE (a, b, max))
+
+/* Return a nonzero value if A is a mathematical multiple of B, where
+   A is unsigned, B is negative, and MAX is the maximum value of A's
+   type.  A's type must be the same as (A % B)'s type.  Normally (A %
+   -B == 0) suffices, but things get tricky if -B would overflow.  */
+#define _GL_UNSIGNED_NEG_MULTIPLE(a, b, max)                            \
+  (((b) < -_GL_SIGNED_INT_MAXIMUM (b)                                   \
+    ? (_GL_SIGNED_INT_MAXIMUM (b) == (max)                              \
+       ? (a)                                                            \
+       : (a) % (_GL_INT_CONVERT (a, _GL_SIGNED_INT_MAXIMUM (b)) + 1))   \
+    : (a) % - (b))                                                      \
+   == 0)
+
+/* Check for integer overflow, and report low order bits of answer.
+
+   The INT_<op>_OVERFLOW macros return 1 if the corresponding C operators
+   might not yield numerically correct answers due to arithmetic overflow.
+   The INT_<op>_WRAPV macros also store the low-order bits of the answer.
+   These macros work correctly on all known practical hosts, and do not rely
+   on undefined behavior due to signed arithmetic overflow.
+
+   Example usage, assuming A and B are long int:
+
+     if (INT_MULTIPLY_OVERFLOW (a, b))
+       printf ("result would overflow\n");
+     else
+       printf ("result is %ld (no overflow)\n", a * b);
+
+   Example usage with WRAPV flavor:
+
+     long int result;
+     bool overflow = INT_MULTIPLY_WRAPV (a, b, &result);
+     printf ("result is %ld (%s)\n", result,
+             overflow ? "after overflow" : "no overflow");
+
+   Restrictions on these macros:
+
+   These macros do not check for all possible numerical problems or
+   undefined or unspecified behavior: they do not check for division
+   by zero, for bad shift counts, or for shifting negative numbers.
+
+   These macros may evaluate their arguments zero or multiple times, so the
+   arguments should not have side effects.
+
+   The WRAPV macros are not constant expressions.  They support only
+   +, binary -, and *.  The result type must be signed.
+
+   These macros are tuned for their last argument being a constant.
+
+   Return 1 if the integer expressions A * B, A - B, -A, A * B, A / B,
+   A % B, and A << B would overflow, respectively.  */
+
+#define INT_ADD_OVERFLOW(a, b) \
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW)
+#define INT_SUBTRACT_OVERFLOW(a, b) \
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_SUBTRACT_OVERFLOW)
+#if _GL_HAS_BUILTIN_OVERFLOW_P
+# define INT_NEGATE_OVERFLOW(a) INT_SUBTRACT_OVERFLOW (0, a)
+#else
+# define INT_NEGATE_OVERFLOW(a) \
+   INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
+#endif
+#define INT_MULTIPLY_OVERFLOW(a, b) \
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_MULTIPLY_OVERFLOW)
+#define INT_DIVIDE_OVERFLOW(a, b) \
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_DIVIDE_OVERFLOW)
+#define INT_REMAINDER_OVERFLOW(a, b) \
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_REMAINDER_OVERFLOW)
+#define INT_LEFT_SHIFT_OVERFLOW(a, b) \
+  INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, \
+                                 _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
+
+/* Return 1 if the expression A <op> B would overflow,
+   where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test,
+   assuming MIN and MAX are the minimum and maximum for the result type.
+   Arguments should be free of side effects.  */
+#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow)        \
+  op_result_overflow (a, b,                                     \
+                      _GL_INT_MINIMUM (0 * (b) + (a)),          \
+                      _GL_INT_MAXIMUM (0 * (b) + (a)))
+
+/* Store the low-order bits of A + B, A - B, A * B, respectively, into *R.
+   Return 1 if the result overflows.  See above for restrictions.  */
+#define INT_ADD_WRAPV(a, b, r) \
+  _GL_INT_OP_WRAPV (a, b, r, +, __builtin_add_overflow, INT_ADD_OVERFLOW)
+#define INT_SUBTRACT_WRAPV(a, b, r) \
+  _GL_INT_OP_WRAPV (a, b, r, -, __builtin_sub_overflow, INT_SUBTRACT_OVERFLOW)
+#define INT_MULTIPLY_WRAPV(a, b, r) \
+  _GL_INT_OP_WRAPV (a, b, r, *, __builtin_mul_overflow, INT_MULTIPLY_OVERFLOW)
+
+/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25390.  See:
+   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68193
+   https://llvm.org/bugs/show_bug.cgi?id=25390
+   For now, assume all versions of GCC-like compilers generate bogus
+   warnings for _Generic.  This matters only for older compilers that
+   lack __builtin_add_overflow.  */
+#if __GNUC__
+# define _GL__GENERIC_BOGUS 1
+#else
+# define _GL__GENERIC_BOGUS 0
+#endif
+
+/* Store the low-order bits of A <op> B into *R, where OP specifies
+   the operation.  BUILTIN is the builtin operation, and OVERFLOW the
+   overflow predicate.  Return 1 if the result overflows.  See above
+   for restrictions.  */
+#if _GL_HAS_BUILTIN_OVERFLOW
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) builtin (a, b, r)
+#elif 201112 <= __STDC_VERSION__ && !_GL__GENERIC_BOGUS
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
+   (_Generic \
+    (*(r), \
+     signed char: \
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                        signed char, SCHAR_MIN, SCHAR_MAX), \
+     short int: \
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                        short int, SHRT_MIN, SHRT_MAX), \
+     int: \
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                        int, INT_MIN, INT_MAX), \
+     long int: \
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
+                        long int, LONG_MIN, LONG_MAX), \
+     long long int: \
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
+                        long long int, LLONG_MIN, LLONG_MAX)))
+#else
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
+   (sizeof *(r) == sizeof (signed char) \
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                       signed char, SCHAR_MIN, SCHAR_MAX) \
+    : sizeof *(r) == sizeof (short int) \
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                       short int, SHRT_MIN, SHRT_MAX) \
+    : sizeof *(r) == sizeof (int) \
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
+                       int, INT_MIN, INT_MAX) \
+    : _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow))
+# ifdef LLONG_MAX
+#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
+    (sizeof *(r) == sizeof (long int) \
+     ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
+                        long int, LONG_MIN, LONG_MAX) \
+     : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
+                        long long int, LLONG_MIN, LLONG_MAX))
+# else
+#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
+    _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
+                     long int, LONG_MIN, LONG_MAX)
+# endif
+#endif
+
+/* Store the low-order bits of A <op> B into *R, where the operation
+   is given by OP.  Use the unsigned type UT for calculation to avoid
+   overflow problems.  *R's type is T, with extrema TMIN and TMAX.
+   T must be a signed integer type.  Return 1 if the result overflows.  */
+#define _GL_INT_OP_CALC(a, b, r, op, overflow, ut, t, tmin, tmax) \
+  (sizeof ((a) op (b)) < sizeof (t) \
+   ? _GL_INT_OP_CALC1 ((t) (a), (t) (b), r, op, overflow, ut, t, tmin, tmax) \
+   : _GL_INT_OP_CALC1 (a, b, r, op, overflow, ut, t, tmin, tmax))
+#define _GL_INT_OP_CALC1(a, b, r, op, overflow, ut, t, tmin, tmax) \
+  ((overflow (a, b) \
+    || (EXPR_SIGNED ((a) op (b)) && ((a) op (b)) < (tmin)) \
+    || (tmax) < ((a) op (b))) \
+   ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \
+   : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0))
+
+/* Return the low-order bits of A <op> B, where the operation is given
+   by OP.  Use the unsigned type UT for calculation to avoid undefined
+   behavior on signed integer overflow, and convert the result to type T.
+   UT is at least as wide as T and is no narrower than unsigned int,
+   T is two's complement, and there is no padding or trap representations.
+   Assume that converting UT to T yields the low-order bits, as is
+   done in all known two's-complement C compilers.  E.g., see:
+   https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html
+
+   According to the C standard, converting UT to T yields an
+   implementation-defined result or signal for values outside T's
+   range.  However, code that works around this theoretical problem
+   runs afoul of a compiler bug in Oracle Studio 12.3 x86.  See:
+   https://lists.gnu.org/r/bug-gnulib/2017-04/msg00049.html
+   As the compiler bug is real, don't try to work around the
+   theoretical problem.  */
+
+#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t) \
+  ((t) ((ut) (a) op (ut) (b)))
+
+#endif /* _GL_INTPROPS_H */
diff --git a/missing_d/mktime.c b/missing_d/mktime.c
index d394ef17..17538a39 100644
--- a/missing_d/mktime.c
+++ b/missing_d/mktime.c
@@ -1,41 +1,50 @@
-/* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+/* Convert a 'struct tm' to a time_t value.
+   Copyright (C) 1993-2018 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
-   Contributed by Paul Eggert (eggert@twinsun.com).
+   Contributed by Paul Eggert <eggert@twinsun.com>.
 
    The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Library General Public License as
-   published by the Free Software Foundation; either version 3 of the
-   License, or (at your option) any later version.
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
 
    The GNU C Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Library General Public License for more details.
+   Lesser General Public License for more details.
 
-   You should have received a copy of the GNU Library General Public
-   License along with the GNU C Library; see the file COPYING.LIB.  If not,
-   write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
-   Boston, MA 02110-1301, USA.  */
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
 
-/* Define this to have a standalone program to test this implementation of
+/* Define this to 1 to have a standalone program to test this implementation of
    mktime.  */
-/* #define DEBUG 1 */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
+#ifndef DEBUG_MKTIME
+# define DEBUG_MKTIME 0
 #endif
 
-#ifdef _LIBC
-# define HAVE_LIMITS_H 1
-# define HAVE_LOCALTIME_R 1
-# define STDC_HEADERS 1
+/* The following macros influence what gets defined when this file is compiled:
+
+   Macro/expression            Which gnulib module    This compilation unit
+                                                      should define
+
+   NEED_MKTIME_WORKING         mktime                 rpl_mktime
+   || NEED_MKTIME_WINDOWS
+
+   NEED_MKTIME_INTERNAL        mktime-internal        mktime_internal
+
+   DEBUG_MKTIME                (defined manually)     my_mktime, main
+ */
+
+#if !defined _LIBC && !DEBUG_MKTIME
+# include <config.h>
 #endif
 
 /* Assume that leap seconds are possible, unless told otherwise.
-   If the host has a `zic' command with a `-L leapsecondfilename' option,
+   If the host has a 'zic' command with a '-L leapsecondfilename' option,
    then it supports leap seconds; otherwise it probably doesn't.  */
 #ifndef LEAP_SECONDS_POSSIBLE
-#define LEAP_SECONDS_POSSIBLE 1
+# define LEAP_SECONDS_POSSIBLE 1
 #endif
 
 #ifndef VMS
@@ -48,54 +57,99 @@
 #if HAVE_LIMITS_H
 #include <limits.h>
 #endif
-
-#if DEBUG
-#include <stdio.h>
-#if STDC_HEADERS
-#include <stdlib.h>
+#if HAVE_STDBOOL_H
+#include <stdbool.h>
 #endif
-/* Make it work even if the system's libc has its own mktime routine.  */
-#define mktime my_mktime
-#endif /* DEBUG */
 
-#ifndef __P
-#if defined (__GNUC__) || (defined (__STDC__) && __STDC__)
-#define __P(args) args
-#else
-#define __P(args) ()
-#endif  /* GCC.  */
-#endif  /* Not __P.  */
+#include <intprops.h>
+#include <verify.h>
 
-#ifndef CHAR_BIT
-#define CHAR_BIT 8
+#if DEBUG_MKTIME
+# include <stdio.h>
+# include <stdlib.h>
+# include <string.h>
+/* Make it work even if the system's libc has its own mktime routine.  */
+# undef mktime
+# define mktime my_mktime
 #endif
 
-#ifndef INT_MIN
-#define INT_MIN (~0 << (sizeof (int) * CHAR_BIT - 1))
-#endif
-#ifndef INT_MAX
-#define INT_MAX (~0 - INT_MIN)
+#if NEED_MKTIME_WINDOWS /* on native Windows */
+# include <stdlib.h>
+# include <string.h>
 #endif
 
-#ifndef TIME_T_MIN
-#define TIME_T_MIN (0 < (time_t) -1 ? (time_t) 0 \
-		    : ~ (time_t) 0 << (sizeof (time_t) * CHAR_BIT - 1))
-#endif
-#ifndef TIME_T_MAX
-#define TIME_T_MAX (~ (time_t) 0 - TIME_T_MIN)
+#if NEED_MKTIME_WORKING || NEED_MKTIME_INTERNAL || DEBUG_MKTIME
+
+/* A signed type that can represent an integer number of years
+   multiplied by three times the number of seconds in a year.  It is
+   needed when converting a tm_year value times the number of seconds
+   in a year.  The factor of three comes because these products need
+   to be subtracted from each other, and sometimes with an offset
+   added to them, without worrying about overflow.
+
+   Much of the code uses long_int to represent time_t values, to
+   lessen the hassle of dealing with platforms where time_t is
+   unsigned, and because long_int should suffice to represent all
+   time_t values that mktime can generate even on platforms where
+   time_t is excessively wide.  */
+
+#if INT_MAX <= LONG_MAX / 3 / 366 / 24 / 60 / 60
+typedef long int long_int;
+#else
+typedef long long int long_int;
 #endif
+verify (INT_MAX <= TYPE_MAXIMUM (long_int) / 3 / 366 / 24 / 60 / 60);
+
+/* Shift A right by B bits portably, by dividing A by 2**B and
+   truncating towards minus infinity.  B should be in the range 0 <= B
+   <= LONG_INT_BITS - 2, where LONG_INT_BITS is the number of useful
+   bits in a long_int.  LONG_INT_BITS is at least 32.
+
+   ISO C99 says that A >> B is implementation-defined if A < 0.  Some
+   implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift
+   right in the usual way when A < 0, so SHR falls back on division if
+   ordinary A >> B doesn't seem to be the usual signed shift.  */
+
+static long_int
+shr (long_int a, int b)
+{
+  long_int one = 1;
+  return (-one >> 1 == -1
+	  ? a >> b
+	  : a / (one << b) - (a % (one << b) < 0));
+}
+
+/* Bounds for the intersection of time_t and long_int.  */
+
+static long_int const mktime_min
+  = ((TYPE_SIGNED (time_t) && TYPE_MINIMUM (time_t) < TYPE_MINIMUM (long_int))
+     ? TYPE_MINIMUM (long_int) : TYPE_MINIMUM (time_t));
+static long_int const mktime_max
+  = (TYPE_MAXIMUM (long_int) < TYPE_MAXIMUM (time_t)
+     ? TYPE_MAXIMUM (long_int) : TYPE_MAXIMUM (time_t));
+
+verify (TYPE_IS_INTEGER (time_t));
 
-#define TM_YEAR_BASE 1900
 #define EPOCH_YEAR 1970
+#define TM_YEAR_BASE 1900
+verify (TM_YEAR_BASE % 100 == 0);
 
-#ifndef __isleap
-/* Nonzero if YEAR is a leap year (every 4 years,
-   except every 100th isn't, and every 400th is).  */
-#define	__isleap(year)	\
-  ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
-#endif
+/* Is YEAR + TM_YEAR_BASE a leap year?  */
+static bool
+leapyear (long_int year)
+{
+  /* Don't add YEAR to TM_YEAR_BASE, as that might overflow.
+     Also, work even if YEAR is negative.  */
+  return
+    ((year & 3) == 0
+     && (year % 100 != 0
+	 || ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3)));
+}
 
 /* How many days come before each month (0-12).  */
+#ifndef _LIBC
+static
+#endif
 const unsigned short int __mon_yday[2][13] =
   {
     /* Normal years.  */
@@ -104,93 +158,180 @@ const unsigned short int __mon_yday[2][13] =
     { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
   };
 
-static time_t ydhms_tm_diff __P ((int, int, int, int, int, const struct tm *));
-time_t __mktime_internal __P ((struct tm *,
-			       struct tm *(*) (const time_t *, struct tm *),
-			       time_t *));
 
+#ifdef _LIBC
+typedef time_t mktime_offset_t;
+#else
+/* Portable standalone applications should supply a <time.h> that
+   declares a POSIX-compliant localtime_r, for the benefit of older
+   implementations that lack localtime_r or have a nonstandard one.
+   See the gnulib time_r module for one way to implement this.  */
+# undef __localtime_r
+# define __localtime_r localtime_r
+# define __mktime_internal mktime_internal
+# include "mktime-internal.h"
+#endif
 
-static struct tm *my_localtime_r __P ((const time_t *, struct tm *));
-static struct tm *
-my_localtime_r (t, tp)
-     const time_t *t;
-     struct tm *tp;
+/* Do the values A and B differ according to the rules for tm_isdst?
+   A and B differ if one is zero and the other positive.  */
+static bool
+isdst_differ (int a, int b)
 {
-  struct tm *l = localtime (t);
-  if (! l)
-    return 0;
-  *tp = *l;
-  return tp;
+  return (!a != !b) && (0 <= a) && (0 <= b);
 }
 
+/* Return an integer value measuring (YEAR1-YDAY1 HOUR1:MIN1:SEC1) -
+   (YEAR0-YDAY0 HOUR0:MIN0:SEC0) in seconds, assuming that the clocks
+   were not adjusted between the timestamps.
+
+   The YEAR values uses the same numbering as TP->tm_year.  Values
+   need not be in the usual range.  However, YEAR1 must not overflow
+   when multiplied by three times the number of seconds in a year, and
+   likewise for YDAY1 and three times the number of seconds in a day.  */
 
-/* Yield the difference between (YEAR-YDAY HOUR:MIN:SEC) and (*TP),
-   measured in seconds, ignoring leap seconds.
-   YEAR uses the same numbering as TM->tm_year.
-   All values are in range, except possibly YEAR.
-   If overflow occurs, yield the low order bits of the correct answer.  */
-static time_t
-ydhms_tm_diff (year, yday, hour, min, sec, tp)
-     int year, yday, hour, min, sec;
-     const struct tm *tp;
+static long_int
+ydhms_diff (long_int year1, long_int yday1, int hour1, int min1, int sec1,
+	    int year0, int yday0, int hour0, int min0, int sec0)
 {
+  verify (-1 / 2 == 0);
+
   /* Compute intervening leap days correctly even if year is negative.
-     Take care to avoid int overflow.  time_t overflow is OK, since
-     only the low order bits of the correct time_t answer are needed.
-     Don't convert to time_t until after all divisions are done, since
-     time_t might be unsigned.  */
-  int a4 = (year >> 2) + (TM_YEAR_BASE >> 2) - ! (year & 3);
-  int b4 = (tp->tm_year >> 2) + (TM_YEAR_BASE >> 2) - ! (tp->tm_year & 3);
+     Take care to avoid integer overflow here.  */
+  int a4 = shr (year1, 2) + shr (TM_YEAR_BASE, 2) - ! (year1 & 3);
+  int b4 = shr (year0, 2) + shr (TM_YEAR_BASE, 2) - ! (year0 & 3);
   int a100 = a4 / 25 - (a4 % 25 < 0);
   int b100 = b4 / 25 - (b4 % 25 < 0);
-  int a400 = a100 >> 2;
-  int b400 = b100 >> 2;
+  int a400 = shr (a100, 2);
+  int b400 = shr (b100, 2);
   int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
-  time_t years = year - (time_t) tp->tm_year;
-  time_t days = (365 * years + intervening_leap_days
-		 + (yday - tp->tm_yday));
-  return (60 * (60 * (24 * days + (hour - tp->tm_hour))
-		+ (min - tp->tm_min))
-	  + (sec - tp->tm_sec));
+
+  /* Compute the desired time without overflowing.  */
+  long_int years = year1 - year0;
+  long_int days = 365 * years + yday1 - yday0 + intervening_leap_days;
+  long_int hours = 24 * days + hour1 - hour0;
+  long_int minutes = 60 * hours + min1 - min0;
+  long_int seconds = 60 * minutes + sec1 - sec0;
+  return seconds;
+}
+
+/* Return the average of A and B, even if A + B would overflow.
+   Round toward positive infinity.  */
+static long_int
+long_int_avg (long_int a, long_int b)
+{
+  return shr (a, 1) + shr (b, 1) + ((a | b) & 1);
 }
 
+/* Return a time_t value corresponding to (YEAR-YDAY HOUR:MIN:SEC),
+   assuming that T corresponds to *TP and that no clock adjustments
+   occurred between *TP and the desired time.
+   Although T and the returned value are of type long_int,
+   they represent time_t values and must be in time_t range.
+   If TP is null, return a value not equal to T; this avoids false matches.
+   YEAR and YDAY must not be so large that multiplying them by three times the
+   number of seconds in a year (or day, respectively) would overflow long_int.
+   If the returned value would be out of range, yield the minimal or
+   maximal in-range value, except do not yield a value equal to T.  */
+static long_int
+guess_time_tm (long_int year, long_int yday, int hour, int min, int sec,
+	       long_int t, const struct tm *tp)
+{
+  if (tp)
+    {
+      long_int result;
+      long_int d = ydhms_diff (year, yday, hour, min, sec,
+			       tp->tm_year, tp->tm_yday,
+			       tp->tm_hour, tp->tm_min, tp->tm_sec);
+      if (! INT_ADD_WRAPV (t, d, &result))
+	return result;
+    }
 
-static time_t localtime_offset;
+  /* Overflow occurred one way or another.  Return the nearest result
+     that is actually in range, except don't report a zero difference
+     if the actual difference is nonzero, as that would cause a false
+     match; and don't oscillate between two values, as that would
+     confuse the spring-forward gap detector.  */
+  return (t < long_int_avg (mktime_min, mktime_max)
+	  ? (t <= mktime_min + 1 ? t + 1 : mktime_min)
+	  : (mktime_max - 1 <= t ? t - 1 : mktime_max));
+}
 
-/* Convert *TP to a time_t value.  */
-time_t
-mktime (tp)
-     struct tm *tp;
+/* Use CONVERT to convert T to a struct tm value in *TM.  T must be in
+   range for time_t.  Return TM if successful, NULL if T is out of
+   range for CONVERT.  */
+static struct tm *
+convert_time (struct tm *(*convert) (const time_t *, struct tm *),
+	      long_int t, struct tm *tm)
 {
-#ifdef _LIBC
-  /* POSIX.1 8.1.1 requires that whenever mktime() is called, the
-     time zone names contained in the external variable `tzname' shall
-     be set as if the tzset() function had been called.  */
-  __tzset ();
-#endif
+  time_t x = t;
+  return convert (&x, tm);
+}
+
+/* Use CONVERT to convert *T to a broken down time in *TP.
+   If *T is out of range for conversion, adjust it so that
+   it is the nearest in-range value and then convert that.
+   A value is in range if it fits in both time_t and long_int.  */
+static struct tm *
+ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
+		long_int *t, struct tm *tp)
+{
+  struct tm *r;
+  if (*t < mktime_min)
+    *t = mktime_min;
+  else if (mktime_max < *t)
+    *t = mktime_max;
+  r = convert_time (convert, *t, tp);
+
+  if (!r && *t)
+    {
+      long_int bad = *t;
+      long_int ok = 0;
+
+      /* BAD is a known unconvertible value, and OK is a known good one.
+	 Use binary search to narrow the range between BAD and OK until
+	 they differ by 1.  */
+      while (true)
+	{
+	  long_int mid = long_int_avg (ok, bad);
+	  if (mid != ok && mid != bad)
+	    break;
+	  r = convert_time (convert, mid, tp);
+	  if (r)
+	    ok = mid;
+	  else
+	    bad = mid;
+	}
+
+      if (!r && ok)
+	{
+	  /* The last conversion attempt failed;
+	     revert to the most recent successful attempt.  */
+	  r = convert_time (convert, ok, tp);
+	}
+    }
 
-  return __mktime_internal (tp, my_localtime_r, &localtime_offset);
+  return r;
 }
 
 /* Convert *TP to a time_t value, inverting
    the monotonic and mostly-unit-linear conversion function CONVERT.
    Use *OFFSET to keep track of a guess at the offset of the result,
    compared to what the result would be for UTC without leap seconds.
-   If *OFFSET's guess is correct, only one CONVERT call is needed.  */
+   If *OFFSET's guess is correct, only one CONVERT call is needed.
+   This function is external because it is used also by timegm.c.  */
 time_t
-__mktime_internal (tp, convert, offset)
-     struct tm *tp;
-     struct tm *(*convert) __P ((const time_t *, struct tm *));
-     time_t *offset;
+__mktime_internal (struct tm *tp,
+		   struct tm *(*convert) (const time_t *, struct tm *),
+		   mktime_offset_t *offset)
 {
-  time_t t, dt, t0;
+  long_int t, gt, t0, t1, t2, dt;
   struct tm tm;
 
   /* The maximum number of probes (calls to CONVERT) should be enough
      to handle any combinations of time zone rule changes, solar time,
-     and leap seconds.  Posix.1 prohibits leap seconds, but some hosts
-     have them anyway.  */
-  int remaining_probes = 4;
+     leap seconds, and oscillations around a spring-forward gap.
+     POSIX.1 prohibits leap seconds, but some hosts have them anyway.  */
+  int remaining_probes = 6;
 
   /* Time requested.  Copy it in case CONVERT modifies *TP; this can
      occur if TP is localtime's returned value and CONVERT is localtime.  */
@@ -202,98 +343,143 @@ __mktime_internal (tp, convert, offset)
   int year_requested = tp->tm_year;
   int isdst = tp->tm_isdst;
 
+  /* 1 if the previous probe was DST.  */
+  int dst2;
+
   /* Ensure that mon is in range, and set year accordingly.  */
   int mon_remainder = mon % 12;
   int negative_mon_remainder = mon_remainder < 0;
   int mon_years = mon / 12 - negative_mon_remainder;
-  int year = year_requested + mon_years;
+  long_int lyear_requested = year_requested;
+  long_int year = lyear_requested + mon_years;
 
   /* The other values need not be in range:
-     the remaining code handles minor overflows correctly,
-     assuming int and time_t arithmetic wraps around.
-     Major overflows are caught at the end.  */
+     the remaining code handles overflows correctly.  */
 
   /* Calculate day of year from year, month, and day of month.
      The result need not be in range.  */
-  int yday = ((__mon_yday[__isleap (year + TM_YEAR_BASE)]
-	       [mon_remainder + 12 * negative_mon_remainder])
-	      + mday - 1);
+  int mon_yday = ((__mon_yday[leapyear (year)]
+		   [mon_remainder + 12 * negative_mon_remainder])
+		  - 1);
+  long_int lmday = mday;
+  long_int yday = mon_yday + lmday;
 
-#if LEAP_SECONDS_POSSIBLE
-  /* Handle out-of-range seconds specially,
-     since ydhms_tm_diff assumes every minute has 60 seconds.  */
-  int sec_requested = sec;
-  if (sec < 0)
-    sec = 0;
-  if (59 < sec)
-    sec = 59;
-#endif
+  int negative_offset_guess;
 
-  /* Invert CONVERT by probing.  First assume the same offset as last time.
-     Then repeatedly use the error to improve the guess.  */
+  int sec_requested = sec;
 
-  tm.tm_year = EPOCH_YEAR - TM_YEAR_BASE;
-  tm.tm_yday = tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
-  t0 = ydhms_tm_diff (year, yday, hour, min, sec, &tm);
+  if (LEAP_SECONDS_POSSIBLE)
+    {
+      /* Handle out-of-range seconds specially,
+	 since ydhms_tm_diff assumes every minute has 60 seconds.  */
+      if (sec < 0)
+	sec = 0;
+      if (59 < sec)
+	sec = 59;
+    }
 
-  for (t = t0 + *offset;
-       (dt = ydhms_tm_diff (year, yday, hour, min, sec, (*convert) (&t, &tm)));
-       t += dt)
-    if (--remaining_probes == 0)
+  /* Invert CONVERT by probing.  First assume the same offset as last
+     time.  */
+
+  INT_SUBTRACT_WRAPV (0, *offset, &negative_offset_guess);
+  t0 = ydhms_diff (year, yday, hour, min, sec,
+		   EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, negative_offset_guess);
+
+  /* Repeatedly use the error to improve the guess.  */
+
+  for (t = t1 = t2 = t0, dst2 = 0;
+       (gt = guess_time_tm (year, yday, hour, min, sec, t,
+			    ranged_convert (convert, &t, &tm)),
+	t != gt);
+       t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0)
+    if (t == t1 && t != t2
+	&& (tm.tm_isdst < 0
+	    || (isdst < 0
+		? dst2 <= (tm.tm_isdst != 0)
+		: (isdst != 0) != (tm.tm_isdst != 0))))
+      /* We can't possibly find a match, as we are oscillating
+	 between two values.  The requested time probably falls
+	 within a spring-forward gap of size GT - T.  Follow the common
+	 practice in this case, which is to return a time that is GT - T
+	 away from the requested time, preferring a time whose
+	 tm_isdst differs from the requested value.  (If no tm_isdst
+	 was requested and only one of the two values has a nonzero
+	 tm_isdst, prefer that value.)  In practice, this is more
+	 useful than returning -1.  */
+      goto offset_found;
+    else if (--remaining_probes == 0)
       return -1;
 
-  /* Check whether tm.tm_isdst has the requested value, if any.  */
-  if (0 <= isdst && 0 <= tm.tm_isdst)
+  /* We have a match.  Check whether tm.tm_isdst has the requested
+     value, if any.  */
+  if (isdst_differ (isdst, tm.tm_isdst))
     {
-      int dst_diff = (isdst != 0) - (tm.tm_isdst != 0);
-      if (dst_diff)
-	{
-	  /* Move two hours in the direction indicated by the disagreement,
-	     probe some more, and switch to a new time if found.
-	     The largest known fallback due to daylight savings is two hours:
-	     once, in Newfoundland, 1988-10-30 02:00 -> 00:00.  */
-	  time_t ot = t - 2 * 60 * 60 * dst_diff;
-	  while (--remaining_probes != 0)
-	    {
-	      struct tm otm;
-	      if (! (dt = ydhms_tm_diff (year, yday, hour, min, sec,
-					 (*convert) (&ot, &otm))))
-		{
-		  t = ot;
-		  tm = otm;
-		  break;
-		}
-	      if ((ot += dt) == t)
-		break;  /* Avoid a redundant probe.  */
-	    }
-	}
+      /* tm.tm_isdst has the wrong value.  Look for a neighboring
+	 time with the right value, and use its UTC offset.
+
+	 Heuristic: probe the adjacent timestamps in both directions,
+	 looking for the desired isdst.  This should work for all real
+	 time zone histories in the tz database.  */
+
+      /* Distance between probes when looking for a DST boundary.  In
+	 tzdata2003a, the shortest period of DST is 601200 seconds
+	 (e.g., America/Recife starting 2000-10-08 01:00), and the
+	 shortest period of non-DST surrounded by DST is 694800
+	 seconds (Africa/Tunis starting 1943-04-17 01:00).  Use the
+	 minimum of these two values, so we don't miss these short
+	 periods when probing.  */
+      int stride = 601200;
+
+      /* The longest period of DST in tzdata2003a is 536454000 seconds
+	 (e.g., America/Jujuy starting 1946-10-01 01:00).  The longest
+	 period of non-DST is much longer, but it makes no real sense
+	 to search for more than a year of non-DST, so use the DST
+	 max.  */
+      int duration_max = 536454000;
+
+      /* Search in both directions, so the maximum distance is half
+	 the duration; add the stride to avoid off-by-1 problems.  */
+      int delta_bound = duration_max / 2 + stride;
+
+      int delta, direction;
+
+      for (delta = stride; delta < delta_bound; delta += stride)
+	for (direction = -1; direction <= 1; direction += 2)
+	  {
+	    long_int ot;
+	    if (! INT_ADD_WRAPV (t, delta * direction, &ot))
+	      {
+		struct tm otm;
+		ranged_convert (convert, &ot, &otm);
+		if (! isdst_differ (isdst, otm.tm_isdst))
+		  {
+		    /* We found the desired tm_isdst.
+		       Extrapolate back to the desired time.  */
+		    t = guess_time_tm (year, yday, hour, min, sec, ot, &otm);
+		    ranged_convert (convert, &t, &tm);
+		    goto offset_found;
+		  }
+	      }
+	  }
     }
 
-  *offset = t - t0;
+ offset_found:
+  /* Set *OFFSET to the low-order bits of T - T0 - NEGATIVE_OFFSET_GUESS.
+     This is just a heuristic to speed up the next mktime call, and
+     correctness is unaffected if integer overflow occurs here.  */
+  INT_SUBTRACT_WRAPV (t, t0, &dt);
+  INT_SUBTRACT_WRAPV (dt, negative_offset_guess, offset);
 
-#if LEAP_SECONDS_POSSIBLE
-  if (sec_requested != tm.tm_sec)
+  if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec)
     {
       /* Adjust time to reflect the tm_sec requested, not the normalized value.
 	 Also, repair any damage from a false match due to a leap second.  */
-      t += sec_requested - sec + (sec == 0 && tm.tm_sec == 60);
-      (*convert) (&t, &tm);
-    }
-#endif
-
-  if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3)
-    {
-      /* time_t isn't large enough to rule out overflows in ydhms_tm_diff,
-	 so check for major overflows.  A gross check suffices,
-	 since if t has overflowed, it is off by a multiple of
-	 TIME_T_MAX - TIME_T_MIN + 1.  So ignore any component of
-	 the difference that is bounded by a small value.  */
-
-      double dyear = (double) year_requested + mon_years - tm.tm_year;
-      double dday = 366 * dyear + mday;
-      double dsec = 60 * (60 * (24 * dday + hour) + min) + sec_requested;
-
-      if (TIME_T_MAX / 3 - TIME_T_MIN / 3 < (dsec < 0 ? - dsec : dsec))
+      long_int sec_adjustment = sec == 0 && tm.tm_sec == 60;
+      sec_adjustment -= sec;
+      sec_adjustment += sec_requested;
+      if (INT_ADD_WRAPV (t, sec_adjustment, &t)
+	  || ! (mktime_min <= t && t <= mktime_max)
+	  || ! convert_time (convert, t, &tm))
 	return -1;
     }
 
@@ -301,16 +487,78 @@ __mktime_internal (tp, convert, offset)
   return t;
 }
 
+#endif /* NEED_MKTIME_WORKING || NEED_MKTIME_INTERNAL || DEBUG_MKTIME */
+
+#if NEED_MKTIME_WORKING || NEED_MKTIME_WINDOWS || DEBUG_MKTIME
+
+# if NEED_MKTIME_WORKING || DEBUG_MKTIME
+static mktime_offset_t localtime_offset;
+# endif
+
+/* Convert *TP to a time_t value.  */
+time_t
+mktime (struct tm *tp)
+{
+# if NEED_MKTIME_WINDOWS
+  /* Rectify the value of the environment variable TZ.
+     There are four possible kinds of such values:
+       - Traditional US time zone names, e.g. "PST8PDT".  Syntax: see
+         <https://msdn.microsoft.com/en-us/library/90s5c885.aspx>
+       - Time zone names based on geography, that contain one or more
+         slashes, e.g. "Europe/Moscow".
+       - Time zone names based on geography, without slashes, e.g.
+         "Singapore".
+       - Time zone names that contain explicit DST rules.  Syntax: see
+         <http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03>
+     The Microsoft CRT understands only the first kind.  It produces incorrect
+     results if the value of TZ is of the other kinds.
+     But in a Cygwin environment, /etc/profile.d/tzset.sh sets TZ to a value
+     of the second kind for most geographies, or of the first kind in a few
+     other geographies.  If it is of the second kind, neutralize it.  For the
+     Microsoft CRT, an absent or empty TZ means the time zone that the user
+     has set in the Windows Control Panel.
+     If the value of TZ is of the third or fourth kind -- Cygwin programs
+     understand these syntaxes as well --, it does not matter whether we
+     neutralize it or not, since these values occur only when a Cygwin user
+     has set TZ explicitly; this case is 1. rare and 2. under the user's
+     responsibility.  */
+  const char *tz = getenv ("TZ");
+  if (tz != NULL && strchr (tz, '/') != NULL)
+    _putenv ("TZ=");
+# endif
+
+# if NEED_MKTIME_WORKING || DEBUG_MKTIME
+#  ifdef _LIBC
+  /* POSIX.1 8.1.1 requires that whenever mktime() is called, the
+     time zone names contained in the external variable 'tzname' shall
+     be set as if the tzset() function had been called.  */
+  __tzset ();
+#  elif HAVE_TZSET
+  tzset ();
+#  endif
+
+  return __mktime_internal (tp, __localtime_r, &localtime_offset);
+# else
+#  undef mktime
+  return mktime (tp);
+# endif
+}
+
+#endif /* NEED_MKTIME_WORKING || NEED_MKTIME_WINDOWS || DEBUG_MKTIME */
+
 #ifdef weak_alias
 weak_alias (mktime, timelocal)
 #endif
+
+#ifdef _LIBC
+libc_hidden_def (mktime)
+libc_hidden_weak (timelocal)
+#endif
 
-#if DEBUG
+#if DEBUG_MKTIME
 
 static int
-not_equal_tm (a, b)
-     struct tm *a;
-     struct tm *b;
+not_equal_tm (const struct tm *a, const struct tm *b)
 {
   return ((a->tm_sec ^ b->tm_sec)
 	  | (a->tm_min ^ b->tm_min)
@@ -318,35 +566,32 @@ not_equal_tm (a, b)
 	  | (a->tm_mday ^ b->tm_mday)
 	  | (a->tm_mon ^ b->tm_mon)
 	  | (a->tm_year ^ b->tm_year)
-	  | (a->tm_mday ^ b->tm_mday)
 	  | (a->tm_yday ^ b->tm_yday)
-	  | (a->tm_isdst ^ b->tm_isdst));
+	  | isdst_differ (a->tm_isdst, b->tm_isdst));
 }
 
 static void
-print_tm (tp)
-     struct tm *tp;
+print_tm (const struct tm *tp)
 {
-  printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
-	  tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
-	  tp->tm_hour, tp->tm_min, tp->tm_sec,
-	  tp->tm_yday, tp->tm_wday, tp->tm_isdst);
+  if (tp)
+    printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
+	    tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
+	    tp->tm_hour, tp->tm_min, tp->tm_sec,
+	    tp->tm_yday, tp->tm_wday, tp->tm_isdst);
+  else
+    printf ("0");
 }
 
 static int
-check_result (tk, tmk, tl, tml)
-     time_t tk;
-     struct tm tmk;
-     time_t tl;
-     struct tm tml;
+check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt)
 {
-  if (tk != tl || not_equal_tm (&tmk, &tml))
+  if (tk != tl || !lt || not_equal_tm (&tmk, lt))
     {
       printf ("mktime (");
-      print_tm (&tmk);
+      print_tm (lt);
       printf (")\nyields (");
-      print_tm (&tml);
-      printf (") == %ld, should be %ld\n", (long) tl, (long) tk);
+      print_tm (&tmk);
+      printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl);
       return 1;
     }
 
@@ -354,15 +599,22 @@ check_result (tk, tmk, tl, tml)
 }
 
 int
-main (argc, argv)
-     int argc;
-     char **argv;
+main (int argc, char **argv)
 {
   int status = 0;
   struct tm tm, tmk, tml;
-  time_t tk, tl;
+  struct tm *lt;
+  time_t tk, tl, tl1;
   char trailer;
 
+  /* Sanity check, plus call tzset.  */
+  tl = 0;
+  if (! localtime (&tl))
+    {
+      printf ("localtime (0) fails\n");
+      status = 1;
+    }
+
   if ((argc == 3 || argc == 4)
       && (sscanf (argv[1], "%d-%d-%d%c",
 		  &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
@@ -376,11 +628,11 @@ main (argc, argv)
       tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
       tmk = tm;
       tl = mktime (&tmk);
-      tml = *localtime (&tl);
-      printf ("mktime returns %ld == ", (long) tl);
+      lt = localtime_r (&tl, &tml);
+      printf ("mktime returns %ld == ", (long int) tl);
       print_tm (&tmk);
       printf ("\n");
-      status = check_result (tl, tmk, tl, tml);
+      status = check_result (tl, tmk, tl, lt);
     }
   else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
     {
@@ -389,21 +641,43 @@ main (argc, argv)
       time_t to = atol (argv[3]);
 
       if (argc == 4)
-	for (tl = from; tl <= to; tl += by)
+	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
 	  {
-	    tml = *localtime (&tl);
-	    tmk = tml;
-	    tk = mktime (&tmk);
-	    status |= check_result (tk, tmk, tl, tml);
+	    lt = localtime_r (&tl, &tml);
+	    if (lt)
+	      {
+		tmk = tml;
+		tk = mktime (&tmk);
+		status |= check_result (tk, tmk, tl, &tml);
+	      }
+	    else
+	      {
+		printf ("localtime_r (%ld) yields 0\n", (long int) tl);
+		status = 1;
+	      }
+	    tl1 = tl + by;
+	    if ((tl1 < tl) != (by < 0))
+	      break;
 	  }
       else
-	for (tl = from; tl <= to; tl += by)
+	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
 	  {
 	    /* Null benchmark.  */
-	    tml = *localtime (&tl);
-	    tmk = tml;
-	    tk = tl;
-	    status |= check_result (tk, tmk, tl, tml);
+	    lt = localtime_r (&tl, &tml);
+	    if (lt)
+	      {
+		tmk = tml;
+		tk = tl;
+		status |= check_result (tk, tmk, tl, &tml);
+	      }
+	    else
+	      {
+		printf ("localtime_r (%ld) yields 0\n", (long int) tl);
+		status = 1;
+	      }
+	    tl1 = tl + by;
+	    if ((tl1 < tl) != (by < 0))
+	      break;
 	  }
     }
   else
@@ -416,10 +690,10 @@ main (argc, argv)
   return status;
 }
 
-#endif /* DEBUG */
+#endif /* DEBUG_MKTIME */
 
 /*
 Local Variables:
-compile-command: "gcc -DDEBUG=1 -Wall -O -g mktime.c -o mktime"
+compile-command: "gcc -DDEBUG_MKTIME -I. -Wall -W -O2 -g mktime.c -o mktime"
 End:
 */
diff --git a/missing_d/mktime.c.old b/missing_d/mktime.c.old
new file mode 100644
index 00000000..d394ef17
--- /dev/null
+++ b/missing_d/mktime.c.old
@@ -0,0 +1,425 @@
+/* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Paul Eggert (eggert@twinsun.com).
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 3 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+/* Define this to have a standalone program to test this implementation of
+   mktime.  */
+/* #define DEBUG 1 */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#ifdef _LIBC
+# define HAVE_LIMITS_H 1
+# define HAVE_LOCALTIME_R 1
+# define STDC_HEADERS 1
+#endif
+
+/* Assume that leap seconds are possible, unless told otherwise.
+   If the host has a `zic' command with a `-L leapsecondfilename' option,
+   then it supports leap seconds; otherwise it probably doesn't.  */
+#ifndef LEAP_SECONDS_POSSIBLE
+#define LEAP_SECONDS_POSSIBLE 1
+#endif
+
+#ifndef VMS
+#include <sys/types.h>		/* Some systems define `time_t' here.  */
+#else
+#include <stddef.h>
+#endif
+#include <time.h>
+
+#if HAVE_LIMITS_H
+#include <limits.h>
+#endif
+
+#if DEBUG
+#include <stdio.h>
+#if STDC_HEADERS
+#include <stdlib.h>
+#endif
+/* Make it work even if the system's libc has its own mktime routine.  */
+#define mktime my_mktime
+#endif /* DEBUG */
+
+#ifndef __P
+#if defined (__GNUC__) || (defined (__STDC__) && __STDC__)
+#define __P(args) args
+#else
+#define __P(args) ()
+#endif  /* GCC.  */
+#endif  /* Not __P.  */
+
+#ifndef CHAR_BIT
+#define CHAR_BIT 8
+#endif
+
+#ifndef INT_MIN
+#define INT_MIN (~0 << (sizeof (int) * CHAR_BIT - 1))
+#endif
+#ifndef INT_MAX
+#define INT_MAX (~0 - INT_MIN)
+#endif
+
+#ifndef TIME_T_MIN
+#define TIME_T_MIN (0 < (time_t) -1 ? (time_t) 0 \
+		    : ~ (time_t) 0 << (sizeof (time_t) * CHAR_BIT - 1))
+#endif
+#ifndef TIME_T_MAX
+#define TIME_T_MAX (~ (time_t) 0 - TIME_T_MIN)
+#endif
+
+#define TM_YEAR_BASE 1900
+#define EPOCH_YEAR 1970
+
+#ifndef __isleap
+/* Nonzero if YEAR is a leap year (every 4 years,
+   except every 100th isn't, and every 400th is).  */
+#define	__isleap(year)	\
+  ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
+#endif
+
+/* How many days come before each month (0-12).  */
+const unsigned short int __mon_yday[2][13] =
+  {
+    /* Normal years.  */
+    { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
+    /* Leap years.  */
+    { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
+  };
+
+static time_t ydhms_tm_diff __P ((int, int, int, int, int, const struct tm *));
+time_t __mktime_internal __P ((struct tm *,
+			       struct tm *(*) (const time_t *, struct tm *),
+			       time_t *));
+
+
+static struct tm *my_localtime_r __P ((const time_t *, struct tm *));
+static struct tm *
+my_localtime_r (t, tp)
+     const time_t *t;
+     struct tm *tp;
+{
+  struct tm *l = localtime (t);
+  if (! l)
+    return 0;
+  *tp = *l;
+  return tp;
+}
+
+
+/* Yield the difference between (YEAR-YDAY HOUR:MIN:SEC) and (*TP),
+   measured in seconds, ignoring leap seconds.
+   YEAR uses the same numbering as TM->tm_year.
+   All values are in range, except possibly YEAR.
+   If overflow occurs, yield the low order bits of the correct answer.  */
+static time_t
+ydhms_tm_diff (year, yday, hour, min, sec, tp)
+     int year, yday, hour, min, sec;
+     const struct tm *tp;
+{
+  /* Compute intervening leap days correctly even if year is negative.
+     Take care to avoid int overflow.  time_t overflow is OK, since
+     only the low order bits of the correct time_t answer are needed.
+     Don't convert to time_t until after all divisions are done, since
+     time_t might be unsigned.  */
+  int a4 = (year >> 2) + (TM_YEAR_BASE >> 2) - ! (year & 3);
+  int b4 = (tp->tm_year >> 2) + (TM_YEAR_BASE >> 2) - ! (tp->tm_year & 3);
+  int a100 = a4 / 25 - (a4 % 25 < 0);
+  int b100 = b4 / 25 - (b4 % 25 < 0);
+  int a400 = a100 >> 2;
+  int b400 = b100 >> 2;
+  int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
+  time_t years = year - (time_t) tp->tm_year;
+  time_t days = (365 * years + intervening_leap_days
+		 + (yday - tp->tm_yday));
+  return (60 * (60 * (24 * days + (hour - tp->tm_hour))
+		+ (min - tp->tm_min))
+	  + (sec - tp->tm_sec));
+}
+
+
+static time_t localtime_offset;
+
+/* Convert *TP to a time_t value.  */
+time_t
+mktime (tp)
+     struct tm *tp;
+{
+#ifdef _LIBC
+  /* POSIX.1 8.1.1 requires that whenever mktime() is called, the
+     time zone names contained in the external variable `tzname' shall
+     be set as if the tzset() function had been called.  */
+  __tzset ();
+#endif
+
+  return __mktime_internal (tp, my_localtime_r, &localtime_offset);
+}
+
+/* Convert *TP to a time_t value, inverting
+   the monotonic and mostly-unit-linear conversion function CONVERT.
+   Use *OFFSET to keep track of a guess at the offset of the result,
+   compared to what the result would be for UTC without leap seconds.
+   If *OFFSET's guess is correct, only one CONVERT call is needed.  */
+time_t
+__mktime_internal (tp, convert, offset)
+     struct tm *tp;
+     struct tm *(*convert) __P ((const time_t *, struct tm *));
+     time_t *offset;
+{
+  time_t t, dt, t0;
+  struct tm tm;
+
+  /* The maximum number of probes (calls to CONVERT) should be enough
+     to handle any combinations of time zone rule changes, solar time,
+     and leap seconds.  Posix.1 prohibits leap seconds, but some hosts
+     have them anyway.  */
+  int remaining_probes = 4;
+
+  /* Time requested.  Copy it in case CONVERT modifies *TP; this can
+     occur if TP is localtime's returned value and CONVERT is localtime.  */
+  int sec = tp->tm_sec;
+  int min = tp->tm_min;
+  int hour = tp->tm_hour;
+  int mday = tp->tm_mday;
+  int mon = tp->tm_mon;
+  int year_requested = tp->tm_year;
+  int isdst = tp->tm_isdst;
+
+  /* Ensure that mon is in range, and set year accordingly.  */
+  int mon_remainder = mon % 12;
+  int negative_mon_remainder = mon_remainder < 0;
+  int mon_years = mon / 12 - negative_mon_remainder;
+  int year = year_requested + mon_years;
+
+  /* The other values need not be in range:
+     the remaining code handles minor overflows correctly,
+     assuming int and time_t arithmetic wraps around.
+     Major overflows are caught at the end.  */
+
+  /* Calculate day of year from year, month, and day of month.
+     The result need not be in range.  */
+  int yday = ((__mon_yday[__isleap (year + TM_YEAR_BASE)]
+	       [mon_remainder + 12 * negative_mon_remainder])
+	      + mday - 1);
+
+#if LEAP_SECONDS_POSSIBLE
+  /* Handle out-of-range seconds specially,
+     since ydhms_tm_diff assumes every minute has 60 seconds.  */
+  int sec_requested = sec;
+  if (sec < 0)
+    sec = 0;
+  if (59 < sec)
+    sec = 59;
+#endif
+
+  /* Invert CONVERT by probing.  First assume the same offset as last time.
+     Then repeatedly use the error to improve the guess.  */
+
+  tm.tm_year = EPOCH_YEAR - TM_YEAR_BASE;
+  tm.tm_yday = tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
+  t0 = ydhms_tm_diff (year, yday, hour, min, sec, &tm);
+
+  for (t = t0 + *offset;
+       (dt = ydhms_tm_diff (year, yday, hour, min, sec, (*convert) (&t, &tm)));
+       t += dt)
+    if (--remaining_probes == 0)
+      return -1;
+
+  /* Check whether tm.tm_isdst has the requested value, if any.  */
+  if (0 <= isdst && 0 <= tm.tm_isdst)
+    {
+      int dst_diff = (isdst != 0) - (tm.tm_isdst != 0);
+      if (dst_diff)
+	{
+	  /* Move two hours in the direction indicated by the disagreement,
+	     probe some more, and switch to a new time if found.
+	     The largest known fallback due to daylight savings is two hours:
+	     once, in Newfoundland, 1988-10-30 02:00 -> 00:00.  */
+	  time_t ot = t - 2 * 60 * 60 * dst_diff;
+	  while (--remaining_probes != 0)
+	    {
+	      struct tm otm;
+	      if (! (dt = ydhms_tm_diff (year, yday, hour, min, sec,
+					 (*convert) (&ot, &otm))))
+		{
+		  t = ot;
+		  tm = otm;
+		  break;
+		}
+	      if ((ot += dt) == t)
+		break;  /* Avoid a redundant probe.  */
+	    }
+	}
+    }
+
+  *offset = t - t0;
+
+#if LEAP_SECONDS_POSSIBLE
+  if (sec_requested != tm.tm_sec)
+    {
+      /* Adjust time to reflect the tm_sec requested, not the normalized value.
+	 Also, repair any damage from a false match due to a leap second.  */
+      t += sec_requested - sec + (sec == 0 && tm.tm_sec == 60);
+      (*convert) (&t, &tm);
+    }
+#endif
+
+  if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3)
+    {
+      /* time_t isn't large enough to rule out overflows in ydhms_tm_diff,
+	 so check for major overflows.  A gross check suffices,
+	 since if t has overflowed, it is off by a multiple of
+	 TIME_T_MAX - TIME_T_MIN + 1.  So ignore any component of
+	 the difference that is bounded by a small value.  */
+
+      double dyear = (double) year_requested + mon_years - tm.tm_year;
+      double dday = 366 * dyear + mday;
+      double dsec = 60 * (60 * (24 * dday + hour) + min) + sec_requested;
+
+      if (TIME_T_MAX / 3 - TIME_T_MIN / 3 < (dsec < 0 ? - dsec : dsec))
+	return -1;
+    }
+
+  *tp = tm;
+  return t;
+}
+
+#ifdef weak_alias
+weak_alias (mktime, timelocal)
+#endif
+
+#if DEBUG
+
+static int
+not_equal_tm (a, b)
+     struct tm *a;
+     struct tm *b;
+{
+  return ((a->tm_sec ^ b->tm_sec)
+	  | (a->tm_min ^ b->tm_min)
+	  | (a->tm_hour ^ b->tm_hour)
+	  | (a->tm_mday ^ b->tm_mday)
+	  | (a->tm_mon ^ b->tm_mon)
+	  | (a->tm_year ^ b->tm_year)
+	  | (a->tm_mday ^ b->tm_mday)
+	  | (a->tm_yday ^ b->tm_yday)
+	  | (a->tm_isdst ^ b->tm_isdst));
+}
+
+static void
+print_tm (tp)
+     struct tm *tp;
+{
+  printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
+	  tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
+	  tp->tm_hour, tp->tm_min, tp->tm_sec,
+	  tp->tm_yday, tp->tm_wday, tp->tm_isdst);
+}
+
+static int
+check_result (tk, tmk, tl, tml)
+     time_t tk;
+     struct tm tmk;
+     time_t tl;
+     struct tm tml;
+{
+  if (tk != tl || not_equal_tm (&tmk, &tml))
+    {
+      printf ("mktime (");
+      print_tm (&tmk);
+      printf (")\nyields (");
+      print_tm (&tml);
+      printf (") == %ld, should be %ld\n", (long) tl, (long) tk);
+      return 1;
+    }
+
+  return 0;
+}
+
+int
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  int status = 0;
+  struct tm tm, tmk, tml;
+  time_t tk, tl;
+  char trailer;
+
+  if ((argc == 3 || argc == 4)
+      && (sscanf (argv[1], "%d-%d-%d%c",
+		  &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
+	  == 3)
+      && (sscanf (argv[2], "%d:%d:%d%c",
+		  &tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer)
+	  == 3))
+    {
+      tm.tm_year -= TM_YEAR_BASE;
+      tm.tm_mon--;
+      tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
+      tmk = tm;
+      tl = mktime (&tmk);
+      tml = *localtime (&tl);
+      printf ("mktime returns %ld == ", (long) tl);
+      print_tm (&tmk);
+      printf ("\n");
+      status = check_result (tl, tmk, tl, tml);
+    }
+  else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
+    {
+      time_t from = atol (argv[1]);
+      time_t by = atol (argv[2]);
+      time_t to = atol (argv[3]);
+
+      if (argc == 4)
+	for (tl = from; tl <= to; tl += by)
+	  {
+	    tml = *localtime (&tl);
+	    tmk = tml;
+	    tk = mktime (&tmk);
+	    status |= check_result (tk, tmk, tl, tml);
+	  }
+      else
+	for (tl = from; tl <= to; tl += by)
+	  {
+	    /* Null benchmark.  */
+	    tml = *localtime (&tl);
+	    tmk = tml;
+	    tk = tl;
+	    status |= check_result (tk, tmk, tl, tml);
+	  }
+    }
+  else
+    printf ("Usage:\
+\t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\
+\t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\
+\t%s FROM BY TO - # Do not test those values (for benchmark).\n",
+	    argv[0], argv[0], argv[0]);
+
+  return status;
+}
+
+#endif /* DEBUG */
+
+/*
+Local Variables:
+compile-command: "gcc -DDEBUG=1 -Wall -O -g mktime.c -o mktime"
+End:
+*/
diff --git a/missing_d/verify.h b/missing_d/verify.h
new file mode 100644
index 00000000..bc7f99db
--- /dev/null
+++ b/missing_d/verify.h
@@ -0,0 +1,284 @@
+/* Compile-time assert-like macros.
+
+   Copyright (C) 2005-2006, 2009-2018 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert, Bruno Haible, and Jim Meyering.  */
+
+#ifndef _GL_VERIFY_H
+#define _GL_VERIFY_H
+
+
+/* Define _GL_HAVE__STATIC_ASSERT to 1 if _Static_assert works as per C11.
+   This is supported by GCC 4.6.0 and later, in C mode, and its use
+   here generates easier-to-read diagnostics when verify (R) fails.
+
+   Define _GL_HAVE_STATIC_ASSERT to 1 if static_assert works as per C++11.
+   This will likely be supported by future GCC versions, in C++ mode.
+
+   Use this only with GCC.  If we were willing to slow 'configure'
+   down we could also use it with other compilers, but since this
+   affects only the quality of diagnostics, why bother?  */
+#if (4 < __GNUC__ + (6 <= __GNUC_MINOR__) \
+     && (201112L <= __STDC_VERSION__  || !defined __STRICT_ANSI__) \
+     && !defined __cplusplus)
+# define _GL_HAVE__STATIC_ASSERT 1
+#endif
+/* The condition (99 < __GNUC__) is temporary, until we know about the
+   first G++ release that supports static_assert.  */
+#if (99 < __GNUC__) && defined __cplusplus
+# define _GL_HAVE_STATIC_ASSERT 1
+#endif
+
+/* FreeBSD 9.1 <sys/cdefs.h>, included by <stddef.h> and lots of other
+   system headers, defines a conflicting _Static_assert that is no
+   better than ours; override it.  */
+#ifndef _GL_HAVE_STATIC_ASSERT
+# include <stddef.h>
+# undef _Static_assert
+#endif
+
+/* Each of these macros verifies that its argument R is nonzero.  To
+   be portable, R should be an integer constant expression.  Unlike
+   assert (R), there is no run-time overhead.
+
+   If _Static_assert works, verify (R) uses it directly.  Similarly,
+   _GL_VERIFY_TRUE works by packaging a _Static_assert inside a struct
+   that is an operand of sizeof.
+
+   The code below uses several ideas for C++ compilers, and for C
+   compilers that do not support _Static_assert:
+
+   * The first step is ((R) ? 1 : -1).  Given an expression R, of
+     integral or boolean or floating-point type, this yields an
+     expression of integral type, whose value is later verified to be
+     constant and nonnegative.
+
+   * Next this expression W is wrapped in a type
+     struct _gl_verify_type {
+       unsigned int _gl_verify_error_if_negative: W;
+     }.
+     If W is negative, this yields a compile-time error.  No compiler can
+     deal with a bit-field of negative size.
+
+     One might think that an array size check would have the same
+     effect, that is, that the type struct { unsigned int dummy[W]; }
+     would work as well.  However, inside a function, some compilers
+     (such as C++ compilers and GNU C) allow local parameters and
+     variables inside array size expressions.  With these compilers,
+     an array size check would not properly diagnose this misuse of
+     the verify macro:
+
+       void function (int n) { verify (n < 0); }
+
+   * For the verify macro, the struct _gl_verify_type will need to
+     somehow be embedded into a declaration.  To be portable, this
+     declaration must declare an object, a constant, a function, or a
+     typedef name.  If the declared entity uses the type directly,
+     such as in
+
+       struct dummy {...};
+       typedef struct {...} dummy;
+       extern struct {...} *dummy;
+       extern void dummy (struct {...} *);
+       extern struct {...} *dummy (void);
+
+     two uses of the verify macro would yield colliding declarations
+     if the entity names are not disambiguated.  A workaround is to
+     attach the current line number to the entity name:
+
+       #define _GL_CONCAT0(x, y) x##y
+       #define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y)
+       extern struct {...} * _GL_CONCAT (dummy, __LINE__);
+
+     But this has the problem that two invocations of verify from
+     within the same macro would collide, since the __LINE__ value
+     would be the same for both invocations.  (The GCC __COUNTER__
+     macro solves this problem, but is not portable.)
+
+     A solution is to use the sizeof operator.  It yields a number,
+     getting rid of the identity of the type.  Declarations like
+
+       extern int dummy [sizeof (struct {...})];
+       extern void dummy (int [sizeof (struct {...})]);
+       extern int (*dummy (void)) [sizeof (struct {...})];
+
+     can be repeated.
+
+   * Should the implementation use a named struct or an unnamed struct?
+     Which of the following alternatives can be used?
+
+       extern int dummy [sizeof (struct {...})];
+       extern int dummy [sizeof (struct _gl_verify_type {...})];
+       extern void dummy (int [sizeof (struct {...})]);
+       extern void dummy (int [sizeof (struct _gl_verify_type {...})]);
+       extern int (*dummy (void)) [sizeof (struct {...})];
+       extern int (*dummy (void)) [sizeof (struct _gl_verify_type {...})];
+
+     In the second and sixth case, the struct type is exported to the
+     outer scope; two such declarations therefore collide.  GCC warns
+     about the first, third, and fourth cases.  So the only remaining
+     possibility is the fifth case:
+
+       extern int (*dummy (void)) [sizeof (struct {...})];
+
+   * GCC warns about duplicate declarations of the dummy function if
+     -Wredundant-decls is used.  GCC 4.3 and later have a builtin
+     __COUNTER__ macro that can let us generate unique identifiers for
+     each dummy function, to suppress this warning.
+
+   * This implementation exploits the fact that older versions of GCC,
+     which do not support _Static_assert, also do not warn about the
+     last declaration mentioned above.
+
+   * GCC warns if -Wnested-externs is enabled and verify() is used
+     within a function body; but inside a function, you can always
+     arrange to use verify_expr() instead.
+
+   * In C++, any struct definition inside sizeof is invalid.
+     Use a template type to work around the problem.  */
+
+/* Concatenate two preprocessor tokens.  */
+#define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y)
+#define _GL_CONCAT0(x, y) x##y
+
+/* _GL_COUNTER is an integer, preferably one that changes each time we
+   use it.  Use __COUNTER__ if it works, falling back on __LINE__
+   otherwise.  __LINE__ isn't perfect, but it's better than a
+   constant.  */
+#if defined __COUNTER__ && __COUNTER__ != __COUNTER__
+# define _GL_COUNTER __COUNTER__
+#else
+# define _GL_COUNTER __LINE__
+#endif
+
+/* Generate a symbol with the given prefix, making it unique if
+   possible.  */
+#define _GL_GENSYM(prefix) _GL_CONCAT (prefix, _GL_COUNTER)
+
+/* Verify requirement R at compile-time, as an integer constant expression
+   that returns 1.  If R is false, fail at compile-time, preferably
+   with a diagnostic that includes the string-literal DIAGNOSTIC.  */
+
+#define _GL_VERIFY_TRUE(R, DIAGNOSTIC) \
+   (!!sizeof (_GL_VERIFY_TYPE (R, DIAGNOSTIC)))
+
+#ifdef __cplusplus
+# if !GNULIB_defined_struct__gl_verify_type
+template <int w>
+  struct _gl_verify_type {
+    unsigned int _gl_verify_error_if_negative: w;
+  };
+#  define GNULIB_defined_struct__gl_verify_type 1
+# endif
+# define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
+    _gl_verify_type<(R) ? 1 : -1>
+#elif defined _GL_HAVE__STATIC_ASSERT
+# define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
+    struct {                                   \
+      _Static_assert (R, DIAGNOSTIC);          \
+      int _gl_dummy;                          \
+    }
+#else
+# define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
+    struct { unsigned int _gl_verify_error_if_negative: (R) ? 1 : -1; }
+#endif
+
+/* Verify requirement R at compile-time, as a declaration without a
+   trailing ';'.  If R is false, fail at compile-time, preferably
+   with a diagnostic that includes the string-literal DIAGNOSTIC.
+
+   Unfortunately, unlike C11, this implementation must appear as an
+   ordinary declaration, and cannot appear inside struct { ... }.  */
+
+#ifdef _GL_HAVE__STATIC_ASSERT
+# define _GL_VERIFY _Static_assert
+#else
+# define _GL_VERIFY(R, DIAGNOSTIC)				       \
+    extern int (*_GL_GENSYM (_gl_verify_function) (void))	       \
+      [_GL_VERIFY_TRUE (R, DIAGNOSTIC)]
+#endif
+
+/* _GL_STATIC_ASSERT_H is defined if this code is copied into assert.h.  */
+#ifdef _GL_STATIC_ASSERT_H
+# if !defined _GL_HAVE__STATIC_ASSERT && !defined _Static_assert
+#  define _Static_assert(R, DIAGNOSTIC) _GL_VERIFY (R, DIAGNOSTIC)
+# endif
+# if !defined _GL_HAVE_STATIC_ASSERT && !defined static_assert
+#  define static_assert _Static_assert /* C11 requires this #define.  */
+# endif
+#endif
+
+/* @assert.h omit start@  */
+
+/* Each of these macros verifies that its argument R is nonzero.  To
+   be portable, R should be an integer constant expression.  Unlike
+   assert (R), there is no run-time overhead.
+
+   There are two macros, since no single macro can be used in all
+   contexts in C.  verify_true (R) is for scalar contexts, including
+   integer constant expression contexts.  verify (R) is for declaration
+   contexts, e.g., the top level.  */
+
+/* Verify requirement R at compile-time, as an integer constant expression.
+   Return 1.  This is equivalent to verify_expr (R, 1).
+
+   verify_true is obsolescent; please use verify_expr instead.  */
+
+#define verify_true(R) _GL_VERIFY_TRUE (R, "verify_true (" #R ")")
+
+/* Verify requirement R at compile-time.  Return the value of the
+   expression E.  */
+
+#define verify_expr(R, E) \
+   (_GL_VERIFY_TRUE (R, "verify_expr (" #R ", " #E ")") ? (E) : (E))
+
+/* Verify requirement R at compile-time, as a declaration without a
+   trailing ';'.  */
+
+#ifdef __GNUC__
+# define verify(R) _GL_VERIFY (R, "verify (" #R ")")
+#else
+/* PGI barfs if R is long.  Play it safe.  */
+# define verify(R) _GL_VERIFY (R, "verify (...)")
+#endif
+
+#ifndef __has_builtin
+# define __has_builtin(x) 0
+#endif
+
+/* Assume that R always holds.  This lets the compiler optimize
+   accordingly.  R should not have side-effects; it may or may not be
+   evaluated.  Behavior is undefined if R is false.  */
+
+#if (__has_builtin (__builtin_unreachable) \
+     || 4 < __GNUC__ + (5 <= __GNUC_MINOR__))
+# define assume(R) ((R) ? (void) 0 : __builtin_unreachable ())
+#elif 1200 <= _MSC_VER
+# define assume(R) __assume (R)
+#elif ((defined GCC_LINT || defined lint) \
+       && (__has_builtin (__builtin_trap) \
+           || 3 < __GNUC__ + (3 < __GNUC_MINOR__ + (4 <= __GNUC_PATCHLEVEL__))))
+  /* Doing it this way helps various packages when configured with
+     --enable-gcc-warnings, which compiles with -Dlint.  It's nicer
+     when 'assume' silences warnings even with older GCCs.  */
+# define assume(R) ((R) ? (void) 0 : __builtin_trap ())
+#else
+# define assume(R) ((void) (0 && (R)))
+#endif
+
+/* @assert.h omit end@  */
+
+#endif