* Makefile.in (gnucompare*): Merge into ...

	(slowcompare*): ... here.
	(fastcompare*): New targets.
	* aclocal.m4 (gcc_AC_PROG_CMP_IGNORE_INITIAL): Add checks for
	other "fast" cmp programs.
	* configure: Regenerate.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@71703 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 14 insertions, 4 deletions

diff --git a/gcc/aclocal.m4 b/gcc/aclocal.m4
index d772ee91f5b..9cd18a17c4c 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
 ])