Set up blank top_srcdir if building in source directory.

This means short, relative names are used for C source files when
compiling in the source directory.

* Makefile (CFLAGS): Exclude -iquote $(top_srcdir) arguments
if top_srcdir is blank. Remove slash after $(top_srcdir),
since the variable includes it now, if its value is not blank.
(SRCS, ABBREV, opt/%-win.o, lex.yy.c, y.tab.c, install): Remove slash
after $(top_srcdir).
(dbg/%.o, opt/%.o): Only include rules for depending
on $(top_srcdir)%.c prerequisite if top_srcdir is not blank.
In the blank case, the rules are redundant.

* configure: if configuring in the root of the source tree,
establish top_srcdir as blank, otherwise establish is as
an absolute path with a trailing slash.

1 files changed, 11 insertions, 4 deletions

diff --git a/configure b/configure
index 6fc5e065..11f30da4 100755
--- a/configure
+++ b/configure
@@ -535,11 +535,18 @@ done
 source_dir="$(dirname $0)"
 
 #
-# Compute an absolute path to the source directory.
+# If building in a separate directory, establish top_srcdir as
+# an absolute path to the source directory, with a trailing slash.
+# Otherwise top_srcdir is blank.
 #
-top_srcdir="$(cd "$source_dir" ; pwd -P)"
 
-printf "Checking source directory %s ..." "$top_srcdir"
+if [ "$source_dir" = "." ] ; then
+  top_srcdir=""
+else
+  top_srcdir="$(cd "$source_dir" ; pwd -P)"/
+fi
+
+printf "Checking source directory \"%s\" ..." "$top_srcdir"
 
 case "$top_srcdir" in
 " "* | *" "* | *" " )
@@ -715,7 +722,7 @@ conftest_syms()
 # But this is pointless if we have no git repo.
 # "have_git" means we have a repo, and git.
 #
-if [ -d $top_srcdir/.git ] ; then 
+if [ -d $top_srcdir.git ] ; then 
   printf "Checking whether we have git ... "
 
   if git --version > /dev/null 2> /dev/null ; then