bisect-runner.pl should patch unreliable C symbol detection code.

Fix Configure's symbol detection to that of commit 373dfab3839ca168 if it's
any intermediate version 5129fff43c4fe08c or later, as the intermediate
versions don't work correctly on (at least) Sparc Linux.

1 files changed, 60 insertions, 0 deletions

diff --git a/Porting/bisect-runner.pl b/Porting/bisect-runner.pl
index 27e56a5be2..50d62d7a6a 100755
--- a/Porting/bisect-runner.pl
+++ b/Porting/bisect-runner.pl
@@ -586,6 +586,66 @@ if ($major < 8 && !extract_from_file('Configure',
               });
 }
 
+if ($major == 8 || $major == 9) {
+    # Fix symbol detection to that of commit 373dfab3839ca168 if it's any
+    # intermediate version 5129fff43c4fe08c or later, as the intermediate
+    # versions don't work correctly on (at least) Sparc Linux.
+    # 5129fff43c4fe08c adds the first mention of mistrustnm.
+    # 373dfab3839ca168 removes the last mention of lc=""
+    edit_file('Configure', sub {
+                  my $code = shift;
+                  return $code
+                      if $code !~ /\btc="";/; # 373dfab3839ca168 or later
+                  return $code
+                      if $code !~ /\bmistrustnm\b/; # before 5129fff43c4fe08c
+                  my $fixed = <<'EOC';
+
+: is a C symbol defined?
+csym='tlook=$1;
+case "$3" in
+-v) tf=libc.tmp; tdc="";;
+-a) tf=libc.tmp; tdc="[]";;
+*) tlook="^$1\$"; tf=libc.list; tdc="()";;
+esac;
+tx=yes;
+case "$reuseval-$4" in
+true-) ;;
+true-*) tx=no; eval "tval=\$$4"; case "$tval" in "") tx=yes;; esac;;
+esac;
+case "$tx" in
+yes)
+	tval=false;
+	if $test "$runnm" = true; then
+		if $contains $tlook $tf >/dev/null 2>&1; then
+			tval=true;
+		elif $test "$mistrustnm" = compile -o "$mistrustnm" = run; then
+			echo "void *(*(p()))$tdc { extern void *$1$tdc; return &$1; } int main() { if(p()) return(0); else return(1); }"> try.c;
+			$cc -o try $optimize $ccflags $ldflags try.c >/dev/null 2>&1 $libs && tval=true;
+			$test "$mistrustnm" = run -a -x try && { $run ./try$_exe >/dev/null 2>&1 || tval=false; };
+			$rm -f try$_exe try.c core core.* try.core;
+		fi;
+	else
+		echo "void *(*(p()))$tdc { extern void *$1$tdc; return &$1; } int main() { if(p()) return(0); else return(1); }"> try.c;
+		$cc -o try $optimize $ccflags $ldflags try.c $libs >/dev/null 2>&1 && tval=true;
+		$rm -f try$_exe try.c;
+	fi;
+	;;
+*)
+	case "$tval" in
+	$define) tval=true;;
+	*) tval=false;;
+	esac;
+	;;
+esac;
+eval "$2=$tval"'
+
+EOC
+                  $code =~ s/\n: is a C symbol defined\?\n.*?\neval "\$2=\$tval"'\n\n/$fixed/sm
+                      or die "substitution failed";
+                  return $code;
+              });
+}
+
 if ($major < 10 && extract_from_file('Configure', qr/^set malloc\.h i_malloc$/)) {
     # This is commit 01d07975f7ef0e7d, trimmed, with $compile inlined as
     # prior to bd9b35c97ad661cc Configure had the malloc.h test before the