libgcc patch committed: Use .init_array for constructor if available

[Ian Lance Taylor]

This libgcc patch changes the morestack support to use the
.init_array.0000 section for the constructor rather than the
.ctors.65535 section, if the target supports .init_array.  This should
avoid pointless mixing .ctors and .init_array.  Bootstrapped and ran
Go and split-stack tests on x86_64-pc-linux-gnu.  Committed to
mainline.

Ian

* config/i386/morestack.S: Use .init_array for constructor if
available.
* config/rs6000/morestack.S: Likewise.
* config/s390/morestack.S: Likewise.
-------------- next part --------------
diff --git a/libgcc/config/i386/morestack.S b/libgcc/config/i386/morestack.S
index 718dbb1d5d2..2e748eda8a7 100644
--- a/libgcc/config/i386/morestack.S
+++ b/libgcc/config/i386/morestack.S
@@ -23,6 +23,7 @@
 # see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # <http://www.gnu.org/licenses/>.
 
+#include "auto-host.h"
 
 # Support for allocating more stack space when using -fsplit-stack.
 # When a function discovers that it needs more stack space, it will
@@ -75,7 +76,7 @@
 # The amount of extra space we ask for.  In general this has to be
 # enough for the dynamic loader to find a symbol and for a signal
 # handler to run.
-	
+
 #ifndef __x86_64__
 #define BACKOFF (1024)
 #else
@@ -160,7 +161,7 @@ __morestack_non_split:
 	cmpb	$0x55,1(%eax)
 	je	2f
 
-3:	
+3:
 	movl	%eax,4(%esp)		# Update return address.
 
 	popl	%eax			# Restore %eax and stack.
@@ -426,7 +427,7 @@ __morestack:
 
 # This is the cleanup code called by the stack unwinder when unwinding
 # through the code between .LEHB0 and .LEHE0 above.
-	
+
 .L1:
 	.cfi_restore_state
 	subl	$16,%esp		# Maintain 16 byte alignment.
@@ -600,7 +601,7 @@ __morestack:
 
 # This is the cleanup code called by the stack unwinder when unwinding
 # through the code between .LEHB0 and .LEHE0 above.
-	
+
 .L1:
 	.cfi_restore_state
 	subq	$16,%rsp		# Maintain 16 byte alignment.
@@ -848,7 +849,11 @@ __morestack_make_guard:
 # Make __stack_split_initialize a high priority constructor.  FIXME:
 # This is ELF specific.
 
+#if HAVE_INITFINI_ARRAY_SUPPORT
+	.section	.init_array.00000,"aw",@progbits
+#else
 	.section	.ctors.65535,"aw",@progbits
+#endif
 
 #ifndef __LP64__
 	.align	4
diff --git a/libgcc/config/rs6000/morestack.S b/libgcc/config/rs6000/morestack.S
index a2e255e5c21..509e506a6de 100644
--- a/libgcc/config/rs6000/morestack.S
+++ b/libgcc/config/rs6000/morestack.S
@@ -24,6 +24,8 @@
 # see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # <http://www.gnu.org/licenses/>.
 
+#include <auto-host.h>
+
 #if _CALL_ELF == 2
 	.abiversion 2
 #define PARAMS 32
@@ -396,7 +398,11 @@ ENTRY0(__morestack_make_guard)
 
 
 # Make __stack_split_initialize a high priority constructor.
+#if HAVE_INITFINI_ARRAY_SUPPORT
+	.section .init_array.00000,"aw",@progbits
+#else
 	.section .ctors.65535,"aw",@progbits
+#endif
 	.p2align 3
 	.quad __stack_split_initialize
 	.quad __morestack_load_mmap
diff --git a/libgcc/config/s390/morestack.S b/libgcc/config/s390/morestack.S
index 80349fd869c..d873de90d12 100644
--- a/libgcc/config/s390/morestack.S
+++ b/libgcc/config/s390/morestack.S
@@ -28,6 +28,8 @@
 # also cover signal frame size.
 #define BACKOFF 0x1000
 
+#include <auto-host.h>
+
 # The __morestack function.
 
 	.global	__morestack
@@ -594,7 +596,11 @@ __morestack_make_guard:
 
 # Make __stack_split_initialize a high priority constructor.
 
+#if HAVE_INITFINI_ARRAY_SUPPORT
+	.section .init_array.00000,"aw",@progbits
+#else
 	.section .ctors.65535,"aw",@progbits
+#endif
 
 #ifndef __LP64__
 	.align	4