# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
+abs_top_srcdir='@abs_top_srcdir@'
+abs_top_builddir='@abs_top_builddir@'
+: ${PERL='@perl@'}
+
# Use the shipped files, not those installed.
-BISON_PKGDATADIR='@abs_top_srcdir@/data'
+BISON_PKGDATADIR=$abs_top_srcdir/data
export BISON_PKGDATADIR
-exec $PREBISON '@abs_top_builddir@/src/bison' ${1+"$@"}
+
+$PREBISON "$abs_top_builddir/src/bison" ${1+"$@"}
+status=$?
+
+# As a special dark magic, if we are actually using this wrapper to
+# compile Bison's src/parse-gram.y, post-process the synclines to
+# avoid dependencies on the user's set up (srcdir vs. builddir).
+for i
+do
+ case $i in
+ */src/parse-gram.y)
+ if $PERL --version >/dev/null; then
+ # We are called by ylwrap which still uses y.tab.*, and
+ # post-processes the synclines on y.tab.c itself. Don't let it
+ # do it. Besides, it leaves "parse-gram.y" as the source,
+ # dropping the src/ part.
+ $PERL -pi -e 's{"y\.tab\.}{"src/parse-gram.}g;' \
+ -e 's{".*/(parse-gram\.y)"}{"src/$1"}g;' \
+ y.tab.[ch]
+ fi
+ ;;
+ esac
+done
+
+exit $status
+
+# Local Variables:
+# mode: shell-script
+# End: