2004-04-28 Paolo Bonzini <bonzini@gnu.org>

        * config/acx.m4: Fix fastcompare support for new-bootstrap.
        * configure: Regenerate.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@81281 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 58 insertions, 21 deletions

diff --git a/ChangeLog b/ChangeLog
index 116abfe41ad..8ba5f3e0839 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2004-04-28  Paolo Bonzini  <bonzini@gnu.org>
+
+	* config/acx.m4: Fix fastcompare support for new-bootstrap.
+	* configure: Regenerate.
+
 2004-04-27  Paolo Bonzini  <bonzini@gnu.org>
 
 	Revert:
diff --git a/config/acx.m4 b/config/acx.m4
index 9b40d4f0771..3652836bb8d 100644
--- a/config/acx.m4
+++ b/config/acx.m4
@@ -193,3 +193,34 @@ else
   have_gnat=no
 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.  We also test
+dnl for the parameter format "cmp file1 file2 skip1 skip2" which is
+dnl accepted by cmp on some systems.
+AC_DEFUN([ACX_PROG_CMP_IGNORE_INITIAL],
+[AC_CACHE_CHECK([how to compare bootstrapped objects], gcc_cv_prog_cmp_skip,
+[ echo abfoo >t1
+  echo cdfoo >t2
+  gcc_cv_prog_cmp_skip='tail +16c $$f1 > tmp-foo1; tail +16c $$f2 > tmp-foo2; cmp tmp-foo1 tmp-foo2'
+  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='cmp $$f1 $$f2 16 16'
+    fi
+  fi
+  if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then
+    if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; then
+      :
+    else
+      gcc_cv_prog_cmp_skip='cmp --ignore-initial=16 $$f1 $$f2'
+    fi
+  fi
+  rm t1 t2
+])
+do_compare="$gcc_cv_prog_cmp_skip"
+AC_SUBST(do_compare)
+])
diff --git a/configure b/configure
index cda8359460a..65ecf0975e0 100755
--- a/configure
+++ b/configure
@@ -1855,7 +1855,7 @@ fi
 # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1860: checking for $ac_word" >&5
+echo "configure:1859: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1885,7 +1885,7 @@ if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1890: checking for $ac_word" >&5
+echo "configure:1889: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1936,7 +1936,7 @@ fi
       # Extract the first word of "cl", so it can be a program name with args.
 set dummy cl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1941: checking for $ac_word" >&5
+echo "configure:1940: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1968,7 +1968,7 @@ fi
 fi
 
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works""... $ac_c" 1>&6
-echo "configure:1973: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
+echo "configure:1972: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
 
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
@@ -1979,12 +1979,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 
 cat > conftest.$ac_ext << EOF
 
-#line 1984 "configure"
+#line 1983 "configure"
 #include "confdefs.h"
 
 main(){return(0);}
 EOF
-if { (eval echo configure:1989: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1988: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   ac_cv_prog_cc_works=yes
   # If we can't run a trivial program, we are probably using a cross compiler.
   if (./conftest; exit) 2>/dev/null; then
@@ -2010,12 +2010,12 @@ if test $ac_cv_prog_cc_works = no; then
   { echo "configure: error: installation or configuration problem: C compiler cannot create executables." 1>&2; exit 1; }
 fi
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler""... $ac_c" 1>&6
-echo "configure:2015: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
+echo "configure:2014: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
 echo "$ac_t""$ac_cv_prog_cc_cross" 1>&6
 cross_compiling=$ac_cv_prog_cc_cross
 
 echo $ac_n "checking whether we are using GNU C""... $ac_c" 1>&6
-echo "configure:2020: checking whether we are using GNU C" >&5
+echo "configure:2019: checking whether we are using GNU C" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2024,7 +2024,7 @@ else
   yes;
 #endif
 EOF
-if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:2029: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
+if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:2028: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
   ac_cv_prog_gcc=yes
 else
   ac_cv_prog_gcc=no
@@ -2043,7 +2043,7 @@ ac_test_CFLAGS="${CFLAGS+set}"
 ac_save_CFLAGS="$CFLAGS"
 CFLAGS=
 echo $ac_n "checking whether ${CC-cc} accepts -g""... $ac_c" 1>&6
-echo "configure:2048: checking whether ${CC-cc} accepts -g" >&5
+echo "configure:2047: checking whether ${CC-cc} accepts -g" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_cc_g'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2079,7 +2079,7 @@ fi
 # Extract the first word of "${ac_tool_prefix}gnatbind", so it can be a program name with args.
 set dummy ${ac_tool_prefix}gnatbind; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:2084: checking for $ac_word" >&5
+echo "configure:2083: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_GNATBIND'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2111,7 +2111,7 @@ if test -n "$ac_tool_prefix"; then
   # Extract the first word of "gnatbind", so it can be a program name with args.
 set dummy gnatbind; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:2116: checking for $ac_word" >&5
+echo "configure:2115: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_GNATBIND'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2144,7 +2144,7 @@ fi
 fi
 
 echo $ac_n "checking whether compiler driver understands Ada""... $ac_c" 1>&6
-echo "configure:2149: checking whether compiler driver understands Ada" >&5
+echo "configure:2148: checking whether compiler driver understands Ada" >&5
 if eval "test \"`echo '$''{'acx_cv_cc_gcc_supports_ada'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2177,22 +2177,23 @@ else
 fi
 
 echo $ac_n "checking how to compare bootstrapped objects""... $ac_c" 1>&6
-echo "configure:2182: checking how to compare bootstrapped objects" >&5
+echo "configure:2181: checking how to compare bootstrapped objects" >&5
 if eval "test \"`echo '$''{'gcc_cv_prog_cmp_skip'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
    echo abfoo >t1
   echo cdfoo >t2
   gcc_cv_prog_cmp_skip='tail +16c $$f1 > tmp-foo1; tail +16c $$f2 > tmp-foo2; cmp tmp-foo1 tmp-foo2'
+  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='cmp $$f1 $$f2 16 16'
+    fi
+  fi
   if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then
     if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; 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='cmp $$f1 $$f2 16 16'
-        fi
-      fi
+      :
     else
       gcc_cv_prog_cmp_skip='cmp --ignore-initial=16 $$f1 $$f2'
     fi