diff options
Diffstat (limited to 'gcc/aclocal.m4')
| -rw-r--r-- | gcc/aclocal.m4 | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/gcc/aclocal.m4 b/gcc/aclocal.m4 index d772ee9..9cd18a1 100644 --- a/gcc/aclocal.m4 +++ b/gcc/aclocal.m4 @@ -104,19 +104,29 @@ fi dnl 'make compare' can be significantly faster, if cmp itself can dnl skip bytes instead of using tail. The test being performed is dnl "if cmp --ignore-initial=2 t1 t2 && ! cmp --ignore-initial=1 t1 t2" -dnl but we need to sink errors and handle broken shells. +dnl but we need to sink errors and handle broken shells. We also test +dnl for the parameter format "cmp file1 file2 skip1 skip2" which is +dnl accepted by cmp on some systems. AC_DEFUN(gcc_AC_PROG_CMP_IGNORE_INITIAL, [AC_CACHE_CHECK([for cmp's capabilities], gcc_cv_prog_cmp_skip, [ echo abfoo >t1 echo cdfoo >t2 + gcc_cv_prog_cmp_skip=slowcompare if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; then - gcc_cv_prog_cmp_skip=slowcompare + : else gcc_cv_prog_cmp_skip=gnucompare fi - else - gcc_cv_prog_cmp_skip=slowcompare + fi + if test $gcc_cv_prog_cmp_skip = slowcompare ; then + if cmp t1 t2 2 2 > /dev/null 2>&1; then + if cmp t1 t2 1 1 > /dev/null 2>&1; then + : + else + gcc_cv_prog_cmp_skip=fastcompare + fi + fi fi rm t1 t2 ]) |