re PR go/66870 (split stack issues on ppc64le and ppc64)

	PR target/66870
	* config/rs6000/sysv4.h (TARGET_CAN_SPLIT_STACK_64BIT): Define.
	* configure.ac: Define HAVE_GOLD_ALTERNATE_SPLIT_STACK on Power
	based on gold linker version.
	* gcc.c: Add -fuse-ld=gold to STACK_SPLIT_SPEC if
	HAVE_GOLD_ALTERNATE_SPLIT_STACK defined.
	* configure, config.in: Regenerate.
go:
	* gospec.c (lang_specific_driver): Set appropriate split stack
	options for 64 bit compiles based on TARGET_CAN_SPLIT_STACK_64BIT.

From-SVN: r228311

2 files changed, 27 insertions, 6 deletions

diff --git a/gcc/go/ChangeLog b/gcc/go/ChangeLog
index 2fa56ab..a6e8dd5 100644
--- a/gcc/go/ChangeLog
+++ b/gcc/go/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-01  Lynn Boger  <laboger@linux.vnet.ibm.com>
+
+	PR target/66870
+	* gospec.c (lang_specific_driver): Set appropriate split stack
+	options for 64 bit compiles based on TARGET_CAN_SPLIT_STACK_64BIT.
+
 2015-09-10  Chris Manghane  <cmang@google.com>
 
 	* go-gcc.cc (Gcc_backend::type_size): Return -1 for
diff --git a/gcc/go/gospec.c b/gcc/go/gospec.c
index 9ccbe75..2c60ee7 100644
--- a/gcc/go/gospec.c
+++ b/gcc/go/gospec.c
@@ -106,6 +106,9 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
   /* The total number of arguments with the new stuff.  */
   int num_args = 1;
 
+  /* Supports split stack */
+  int supports_split_stack = 0;
+
   /* Whether the -o option was used.  */
   bool saw_opt_o = false;
 
@@ -117,6 +120,9 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
   /* Whether the -S option was used.  */
   bool saw_opt_S = false;
 
+  /* Whether the -m32 option was used. */
+  bool saw_opt_m32 ATTRIBUTE_UNUSED = false;
+
   /* The first input file with an extension of .go.  */
   const char *first_go_file = NULL;  
 
@@ -152,6 +158,10 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
 	    library = (library == 0) ? 1 : library;
 	  break;
 
+	case OPT_m32:
+	  saw_opt_m32 = true;
+	  break;
+
 	case OPT_pg:
 	case OPT_p:
 	  saw_profile_flag = true;
@@ -236,15 +246,22 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
   /* Copy the 0th argument, i.e., the name of the program itself.  */
   new_decoded_options[j++] = decoded_options[i++];
 
-  /* If we are linking, pass -fsplit-stack if it is supported.  */
 #ifdef TARGET_CAN_SPLIT_STACK
-  if (library >= 0)
+  supports_split_stack = 1;
+#endif
+
+#ifdef TARGET_CAN_SPLIT_STACK_64BIT
+  if (!saw_opt_m32)
+    supports_split_stack = 1;
+#endif
+
+  /* If we are linking, pass -fsplit-stack if it is supported.  */
+  if ((library >= 0) && supports_split_stack)
     {
       generate_option (OPT_fsplit_stack, NULL, 1, CL_DRIVER,
 		       &new_decoded_options[j]);
       j++;
     }
-#endif
 
   /* NOTE: We start at 1 now, not 0.  */
   while (i < argc)
@@ -381,19 +398,17 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
     generate_option (OPT_shared_libgcc, NULL, 1, CL_DRIVER,
 		     &new_decoded_options[j++]);
 
-#ifdef TARGET_CAN_SPLIT_STACK
   /* libgcc wraps pthread_create to support split stack, however, due to
      relative ordering of -lpthread and -lgcc, we can't just mark
      __real_pthread_create in libgcc as non-weak.  But we need to link in
      pthread_create from pthread if we are statically linking, so we work-
      around by passing -u pthread_create to the linker. */
-  if (static_link)
+  if (static_link && supports_split_stack)
     {
       generate_option (OPT_Wl_, "-u,pthread_create", 1, CL_DRIVER,
 		       &new_decoded_options[j]);
       j++;
     }
-#endif
 
 #if defined(TARGET_SOLARIS) && !defined(USE_GLD)
   /* We use a common symbol for go$zerovalue.  On Solaris, when not