[PATCH] Only use -z relro if it actually does something

[Jakub Jelinek]

Hi!

On ia64 ATM -z relro does nothing (but increase the size of program
headers).
H.J. disabled it because it interferred with linker relaxation
(not sure if that still applies or what the testcase was).

This patch makes glibc use -z relro only when the linker does something
with it.

2004-09-20  Jakub Jelinek  <jakub@redhat.com>

	* configure.in (libc_cv_z_relro): Only set to yes if linker script
	contains DATA_SEGMENT_RELRO_END.
	* configure: Rebuilt.

--- libc/configure.in.jj	2004-09-20 15:16:27.000000000 +0200
+++ libc/configure.in	2004-09-20 15:19:51.950223522 +0200
@@ -1325,11 +1325,13 @@ EOF
 
   AC_CACHE_CHECK(for -z relro option,
 		 libc_cv_z_relro, [dnl
+  libc_cv_z_relro=no
   if AC_TRY_COMMAND([${CC-cc} -v --help 2>&1|grep "z relro" 1>&AS_MESSAGE_LOG_FD])
   then
-    libc_cv_z_relro=yes
-  else
-    libc_cv_z_relro=no
+    if AC_TRY_COMMAND([${CC-cc} -Wl,--verbose 2>&1|grep DATA_SEGMENT_RELRO_END 1>&AS_MESSAGE_LOG_FD])
+    then
+      libc_cv_z_relro=yes
+    fi
   fi])
   AC_SUBST(libc_cv_z_relro)
   if test $libc_cv_z_relro = yes; then
--- libc/configure.jj	2004-09-20 15:16:27.000000000 +0200
+++ libc/configure	2004-09-20 15:19:56.117482738 +0200
@@ -5549,16 +5549,23 @@ echo $ECHO_N "checking for -z relro opti
 if test "${libc_cv_z_relro+set}" = set; then
   echo $ECHO_N "(cached) $ECHO_C" >&6
 else
-    if { ac_try='${CC-cc} -v --help 2>&1|grep "z relro" 1>&5'
+    libc_cv_z_relro=no
+  if { ac_try='${CC-cc} -v --help 2>&1|grep "z relro" 1>&5'
   { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
   (eval $ac_try) 2>&5
   ac_status=$?
   echo "$as_me:$LINENO: \$? = $ac_status" >&5
   (exit $ac_status); }; }
   then
-    libc_cv_z_relro=yes
-  else
-    libc_cv_z_relro=no
+    if { ac_try='${CC-cc} -Wl,--verbose 2>&1|grep DATA_SEGMENT_RELRO_END 1>&5'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }
+    then
+      libc_cv_z_relro=yes
+    fi
   fi
 fi
 echo "$as_me:$LINENO: result: $libc_cv_z_relro" >&5


	Jakub