Disable string merging with alignment > 1 before Solaris 11.4/SPARC

	* configure.ac (gcc_cv_ld_aligned_shf_merge): New test.
	* configure: Regenerate.
	* config.in: Regenerate.
	* varasm.c (mergeable_string_section): Use readonly_data_section
	if linker doesn't support SHF_MERGE with alignment > 8.
	(mergeable_constant_section): Likewise.

From-SVN: r265456

gcc/ChangeLog

+2018-10-24  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
+
+	* configure.ac (gcc_cv_ld_aligned_shf_merge): New test.
+	* configure: Regenerate.
+	* config.in: Regenerate.
+	* varasm.c (mergeable_string_section): Use readonly_data_section
+	if linker doesn't support SHF_MERGE with alignment > 8.
+	(mergeable_constant_section): Likewise.
+
 2018-10-24  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/84013

gcc/config.in

@@ -55,8 +55,7 @@
 #endif
 
 
-/* Define to larger than zero set to the default stack clash protector size as
-   a power of two in bytes. */
+/* Define to larger than zero set the default stack clash protector size. */
 #ifndef USED_FOR_TARGET
 #undef DEFAULT_STK_CLASH_GUARD_SIZE
 #endif
@@ -1430,6 +1429,13 @@
 #endif
 
 
+/* Define 0/1 if your linker supports the SHF_MERGE flag with section
+   alignment > 1. */
+#ifndef USED_FOR_TARGET
+#undef HAVE_LD_ALIGNED_SHF_MERGE
+#endif
+
+
 /* Define if your linker supports --as-needed/--no-as-needed or equivalent
    options. */
 #ifndef USED_FOR_TARGET
@@ -1993,13 +1999,7 @@
 #endif
 
 
-/* Define if we should link with --large-address-aware by default */
-#ifndef USED_FOR_TARGET
-#undef MINGW_DEFAULT_LARGE_ADDR_AWARE
-#endif
-
-
-/* Define if we should link with --large-address-aware by default */
+/* Define if we should link mingw executables with --large-address-aware */
 #ifndef USED_FOR_TARGET
 #undef MINGW_DEFAULT_LARGE_ADDR_AWARE
 #endif

gcc/configure

@@ -23739,6 +23739,30 @@ cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+gcc_cv_ld_aligned_shf_merge=yes
+case "$target" in
+  # While Solaris 10/SPARC ld isn't affected, disable to avoid problems
+  # relinking on Solaris 11 < 11.4.
+  sparc*-*-solaris2.10*)
+    if test x"$gnu_ld" = xno; then
+      gcc_cv_ld_aligned_shf_merge=no
+    fi
+    ;;
+  # SHF_MERGE support is broken in Solaris ld up to Solaris 11.3/SPARC for
+  # alignment > 1.
+  sparc*-*-solaris2.11*)
+    if test x"$gnu_ld" = xno \
+       && test "$ld_vers_major" -lt 2 && test "$ld_vers_minor" -lt 3159; then
+      gcc_cv_ld_aligned_shf_merge=no
+    fi
+    ;;
+esac
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_LD_ALIGNED_SHF_MERGE `if test $gcc_cv_ld_aligned_shf_merge = yes; then echo 1; else echo 0; fi`
+_ACEOF
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for stabs directive" >&5
 $as_echo_n "checking assembler for stabs directive... " >&6; }
 if test "${gcc_cv_as_stabs_directive+set}" = set; then :

gcc/configure.ac

@@ -3039,6 +3039,28 @@ AC_DEFINE_UNQUOTED(HAVE_GAS_SHF_MERGE,
   [`if test $gcc_cv_as_shf_merge = yes; then echo 1; else echo 0; fi`],
 [Define 0/1 if your assembler supports marking sections with SHF_MERGE flag.])
 
+gcc_cv_ld_aligned_shf_merge=yes
+case "$target" in
+  # While Solaris 10/SPARC ld isn't affected, disable to avoid problems
+  # relinking on Solaris 11 < 11.4.
+  sparc*-*-solaris2.10*)
+    if test x"$gnu_ld" = xno; then
+      gcc_cv_ld_aligned_shf_merge=no
+    fi
+    ;;
+  # SHF_MERGE support is broken in Solaris ld up to Solaris 11.3/SPARC for
+  # alignment > 1.
+  sparc*-*-solaris2.11*)
+    if test x"$gnu_ld" = xno \
+       && test "$ld_vers_major" -lt 2 && test "$ld_vers_minor" -lt 3159; then
+      gcc_cv_ld_aligned_shf_merge=no
+    fi
+    ;;
+esac
+AC_DEFINE_UNQUOTED(HAVE_LD_ALIGNED_SHF_MERGE,
+  [`if test $gcc_cv_ld_aligned_shf_merge = yes; then echo 1; else echo 0; fi`],
+[Define 0/1 if your linker supports the SHF_MERGE flag with section alignment > 1.])
+
 gcc_GAS_CHECK_FEATURE([stabs directive], gcc_cv_as_stabs_directive, ,,
 [.stabs "gcc2_compiled.",60,0,0,0],,
 [AC_DEFINE(HAVE_AS_STABS_DIRECTIVE, 1,

gcc/varasm.c

@@ -823,6 +823,9 @@ mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
 	  if (align < modesize)
 	    align = modesize;
 
+	  if (!HAVE_LD_ALIGNED_SHF_MERGE && align > 8)
+	    return readonly_data_section;
+
 	  str = TREE_STRING_POINTER (decl);
 	  unit = GET_MODE_SIZE (mode);
 
@@ -861,7 +864,8 @@ mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
       && known_le (GET_MODE_BITSIZE (mode), align)
       && align >= 8
       && align <= 256
-      && (align & (align - 1)) == 0)
+      && (align & (align - 1)) == 0
+      && (HAVE_LD_ALIGNED_SHF_MERGE ? 1 : align == 8))
     {
       const char *prefix = function_mergeable_rodata_prefix ();
       char *name = (char *) alloca (strlen (prefix) + 30);