Fix a bug in retrieving unset variables through SYMTAB.

10 files changed, 73 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 32aa228d..496c341d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,12 @@
 	* interpret.h (Op_assign_concat): Handle newly created node
 	better.
 
+	Unrelated:
+
+	* interpret.h (Op_subscript): When retrieving from SYMTAB, check
+	for Node_var_new; variables can exist but have not been assigned
+	a value.
+
 2019-12-22         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* config.guess: Updated from GNULIB.
diff --git a/interpret.h b/interpret.h
index 4a7979bd..d157b5b2 100644
--- a/interpret.h
+++ b/interpret.h
@@ -288,6 +288,11 @@ uninitialized_scalar:
 				}
 				if (r->type == Node_var)
 					r = r->var_value;
+				else if (r->type == Node_var_new) {
+					// variable may exist but have never been set.
+					r->var_value = dupnode(Nnull_string);
+					r = r->var_value;
+				}
 			}
 
 			if (r->type == Node_val)
diff --git a/test/ChangeLog b/test/ChangeLog
index f0eac9bd..05e60edc 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -2,6 +2,9 @@
 
 	* indirectbuiltin.awk, numrange.awk, numrange.ok: Changes
 	after code changes.
+	* Makefile.am (EXTRA_DIST): New tests, stupid1 and stupid2.
+	* stupid1.awk, stupid1.ok: New files.
+	* stupid2.awk, stupid2.ok: New files.
 
 2019-11-09         Alexey Pawlow        <alexey.pawlow@gmail.com>
 
@@ -10,30 +13,30 @@
 
 2019-11-03         Arnold D. Robbins     <arnold@skeeve.com>
 
-	* Makefile.am (EXTRA_DISTS): New test, fpat7.
+	* Makefile.am (EXTRA_DIST): New test, fpat7.
 	* fpat7.awk, fpat7.ok, fpat7.in: New files.
 
 2019-10-13         Arnold D. Robbins     <arnold@skeeve.com>
 
-	* Makefile.am (EXTRA_DISTS): New tests, typedregex5 and
+	* Makefile.am (EXTRA_DIST): New tests, typedregex5 and
 	typedregex6.
 	* typedregex5.awk, typedregex5.ok, typedregex6.in,
 	typedregex5.in, typedregex6.awk, typedregex6.ok: New files.
 
 2019-09-24         Jürgen Kahrs Google   <juergen.kahrs@googlemail.com>
 
-	* Makefile.am (EXTRA_DISTS): New test, mpfranswer42.
+	* Makefile.am (EXTRA_DIST): New test, mpfranswer42.
 	* mpfranswer42.awk, mpfranswer42.ok: New files.
 
 2019-07-23         Arnold D. Robbins     <arnold@skeeve.com>
 
-	* Makefile.am (EXTRA_DISTS): Fix typos in filenames.
+	* Makefile.am (EXTRA_DIST): Fix typos in filenames.
 
 2019-06-28         Michal Jaegermann     <michal.jnn@gmail.com>
 
 	Add backwards compatibility tests for inplace.
 
-	* Makefile.am (EXTRA_DISTS): New tests, inplace2bcomp, inplace2bcomp.
+	* Makefile.am (EXTRA_DIST): New tests, inplace2bcomp, inplace2bcomp.
 	* inplace2bcomp.1.ok, test/inplace2bcomp.1.orig.ok,
 	test/inplace2bcomp.2.ok, test/inplace2bcomp.2.orig.ok,
 	test/inplace2bcomp.ok, test/inplace3bcomp.1.ok,
diff --git a/test/Makefile.am b/test/Makefile.am
index c6e33ddb..14e5b0a5 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -1172,6 +1172,10 @@ EXTRA_DIST = \
 	strtonum.ok \
 	strtonum1.awk \
 	strtonum1.ok \
+	stupid1.awk \
+	stupid1.ok \
+	stupid2.awk \
+	stupid2.ok \
 	subamp.awk \
 	subamp.in \
 	subamp.ok \
@@ -1390,7 +1394,9 @@ GAWK_EXT_TESTS = \
 	rsstart1 rsstart2 rsstart3 rstest6 \
 	sandbox1 shadow shadowbuiltin sortfor sortfor2 sortu \
 	sourcesplit split_after_fpat \
-	splitarg4 strftfld strftime strtonum strtonum1 switch2 symtab1 symtab2 \
+	splitarg4 strftfld strftime strtonum strtonum1 \
+	stupid1 stupid2 \
+	switch2 symtab1 symtab2 \
 	symtab3 symtab4 symtab5 symtab6 symtab7 symtab8 symtab9 symtab10 \
 	timeout typedregex1 typedregex2 typedregex3 typedregex4 \
 	typedregex5 typedregex6 \
diff --git a/test/Makefile.in b/test/Makefile.in
index 52b487b6..0fae9058 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -1431,6 +1431,10 @@ EXTRA_DIST = \
 	strtonum.ok \
 	strtonum1.awk \
 	strtonum1.ok \
+	stupid1.awk \
+	stupid1.ok \
+	stupid2.awk \
+	stupid2.ok \
 	subamp.awk \
 	subamp.in \
 	subamp.ok \
@@ -1649,7 +1653,9 @@ GAWK_EXT_TESTS = \
 	rsstart1 rsstart2 rsstart3 rstest6 \
 	sandbox1 shadow shadowbuiltin sortfor sortfor2 sortu \
 	sourcesplit split_after_fpat \
-	splitarg4 strftfld strftime strtonum strtonum1 switch2 symtab1 symtab2 \
+	splitarg4 strftfld strftime strtonum strtonum1 \
+	stupid1 stupid2 \
+	switch2 symtab1 symtab2 \
 	symtab3 symtab4 symtab5 symtab6 symtab7 symtab8 symtab9 symtab10 \
 	timeout typedregex1 typedregex2 typedregex3 typedregex4 \
 	typedregex5 typedregex6 \
@@ -4748,6 +4754,16 @@ strtonum1:
 	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
 	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
 
+stupid1:
+	@echo $@
+	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
+	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
+
+stupid2:
+	@echo $@
+	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
+	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
+
 switch2:
 	@echo $@
 	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
diff --git a/test/Maketests b/test/Maketests
index 627d6ecf..6c8ebf08 100644
--- a/test/Maketests
+++ b/test/Maketests
@@ -1911,6 +1911,16 @@ strtonum1:
 	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
 	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
 
+stupid1:
+	@echo $@
+	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
+	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
+
+stupid2:
+	@echo $@
+	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
+	@-$(CMP) "$(srcdir)"/$@.ok _$@ && rm -f _$@
+
 switch2:
 	@echo $@
 	@AWKPATH="$(srcdir)" $(AWK) -f $@.awk  >_$@ 2>&1 || echo EXIT CODE: $$? >>_$@
diff --git a/test/stupid1.awk b/test/stupid1.awk
new file mode 100644
index 00000000..9881ac6a
--- /dev/null
+++ b/test/stupid1.awk
@@ -0,0 +1,13 @@
+BEGIN {
+	abc("varname")
+	varname
+}
+
+func abc(n)
+{
+	if (n in SYMTAB) {
+		print "before"
+		is = SYMTAB[n]
+		print "after"
+	}
+}
diff --git a/test/stupid1.ok b/test/stupid1.ok
new file mode 100644
index 00000000..eecca907
--- /dev/null
+++ b/test/stupid1.ok
@@ -0,0 +1,2 @@
+before
+after
diff --git a/test/stupid2.awk b/test/stupid2.awk
new file mode 100644
index 00000000..3f6d0d85
--- /dev/null
+++ b/test/stupid2.awk
@@ -0,0 +1,5 @@
+BEGIN {
+	n = "varname"
+	SYMTAB[n]
+	varname
+}
diff --git a/test/stupid2.ok b/test/stupid2.ok
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/test/stupid2.ok