[gofrontend] libgo: If compiler can split-stack and linker can not, use -fno-split-stack.

[Ian Lance Taylor (Gerrit)]

Ian Lance Taylor uploaded a change:
https://go-review.googlesource.com/14598

libgo: If compiler can split-stack and linker can not, use -fno-split-stack.

If the compiler supports split-stack but we are using a gold linker that
does not, as happens on PPC with current GCC but old gold, then we need
to compile the Go code with -fno-split-stack to avoid a linker error
avoid the inability to call from split-stack code to non-split-stack
code.

Change-Id: I2afcaf355ed242d40c0bb77bd32faa795e79faea
---
M libgo/Makefile.am
M libgo/Makefile.in
M libgo/configure
M libgo/configure.ac
M libgo/testsuite/Makefile.in
5 files changed, 23 insertions(+), 4 deletions(-)



diff --git a/libgo/Makefile.am b/libgo/Makefile.am
index 924dba0..ca2280d 100644
--- a/libgo/Makefile.am
+++ b/libgo/Makefile.am
@@ -2074,7 +2074,7 @@
LTLDFLAGS = $(shell $(SHELL) $(top_srcdir)/../libtool-ldflags $(LDFLAGS))

GOCFLAGS = $(CFLAGS)
-AM_GOCFLAGS = $(STRINGOPS_FLAG)
+AM_GOCFLAGS = $(STRINGOPS_FLAG) $(GO_SPLIT_STACK)
GOCOMPILE = $(GOC) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_GOCFLAGS)
$(GOCFLAGS)

LTGOCOMPILE = $(LIBTOOL) --tag GO --mode=compile $(GOC) $(INCLUDES) \
diff --git a/libgo/Makefile.in b/libgo/Makefile.in
index 5072ceb..5d7b8c9 100644
--- a/libgo/Makefile.in
+++ b/libgo/Makefile.in
@@ -366,6 +366,7 @@
GOOS = @GOOS@
GO_LIBCALL_OS_ARCH_FILE = @GO_LIBCALL_OS_ARCH_FILE@
GO_LIBCALL_OS_FILE = @GO_LIBCALL_OS_FILE@
+GO_SPLIT_STACK = @GO_SPLIT_STACK@
GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
GREP = @GREP@
@@ -2153,7 +2154,7 @@
libnetgo_a_SOURCES = $(go_netgo_files)
libnetgo_a_LIBADD = netgo.o
LTLDFLAGS = $(shell $(SHELL) $(top_srcdir)/../libtool-ldflags $(LDFLAGS))
-AM_GOCFLAGS = $(STRINGOPS_FLAG)
+AM_GOCFLAGS = $(STRINGOPS_FLAG) $(GO_SPLIT_STACK)
GOCOMPILE = $(GOC) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_GOCFLAGS)
$(GOCFLAGS)
LTGOCOMPILE = $(LIBTOOL) --tag GO --mode=compile $(GOC) $(INCLUDES) \
$(AM_GOCFLAGS) $(GOCFLAGS)
diff --git a/libgo/configure b/libgo/configure
index 9c79574..3dfa1d8 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -620,6 +620,7 @@
MATH_LIBS
GOC_IS_LLGO_FALSE
GOC_IS_LLGO_TRUE
+GO_SPLIT_STACK
USING_SPLIT_STACK_FALSE
USING_SPLIT_STACK_TRUE
SPLIT_STACK
@@ -11123,7 +11124,7 @@
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11126 "configure"
+#line 11127 "configure"
#include "confdefs.h"

#if HAVE_DLFCN_H
@@ -11229,7 +11230,7 @@
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11232 "configure"
+#line 11233 "configure"
#include "confdefs.h"

#if HAVE_DLFCN_H
@@ -14050,6 +14051,13 @@
fi


+if test "$libgo_cv_c_split_stack_supported" = yes
-a "$libgo_cv_c_linker_split_non_split" = no; then
+ GO_SPLIT_STACK=-fno-split-stack
+else
+ GO_SPLIT_STACK=
+fi
+
+
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether linker supports
split stack" >&5
$as_echo_n "checking whether linker supports split stack... " >&6; }
if test "${libgo_cv_c_linker_supports_split_stack+set}" = set; then :
diff --git a/libgo/configure.ac b/libgo/configure.ac
index ca5325a..15814ba 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -407,6 +407,15 @@
AM_CONDITIONAL(USING_SPLIT_STACK,
test "$libgo_cv_c_split_stack_supported" = yes
-a "$libgo_cv_c_linker_split_non_split" = yes)

+dnl If the compiler supports split-stack but the linker does not, then
+dnl we need to explicitly disable split-stack for Go.
+if test "$libgo_cv_c_split_stack_supported" = yes
-a "$libgo_cv_c_linker_split_non_split" = no; then
+ GO_SPLIT_STACK=-fno-split-stack
+else
+ GO_SPLIT_STACK=
+fi
+AC_SUBST(GO_SPLIT_STACK)
+
dnl Check whether the linker does stack munging when calling from
dnl split-stack into non-split-stack code. We check this by looking
dnl at the --help output. FIXME: This is only half right: it's
diff --git a/libgo/testsuite/Makefile.in b/libgo/testsuite/Makefile.in
index b4547a3..ba04a50 100644
--- a/libgo/testsuite/Makefile.in
+++ b/libgo/testsuite/Makefile.in
@@ -108,6 +108,7 @@
GOOS = @GOOS@
GO_LIBCALL_OS_ARCH_FILE = @GO_LIBCALL_OS_ARCH_FILE@
GO_LIBCALL_OS_FILE = @GO_LIBCALL_OS_FILE@
+GO_SPLIT_STACK = @GO_SPLIT_STACK@
GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
GREP = @GREP@

--
https://go-review.googlesource.com/14598

[Ian Lance Taylor (Gerrit)]

Ian Lance Taylor has posted comments on this change.

libgo: If compiler can split-stack and linker can not, use -fno-split-stack.

Patch Set 1: Code-Review+2

--
https://go-review.googlesource.com/14598
Gerrit-Reviewer: Ian Lance Taylor <ia...@golang.org>
Gerrit-HasComments: No

[Ian Lance Taylor (Gerrit)]

Ian Lance Taylor has submitted this change and it was merged.

libgo: If compiler can split-stack and linker can not, use -fno-split-stack.

If the compiler supports split-stack but we are using a gold linker that
does not, as happens on PPC with current GCC but old gold, then we need
to compile the Go code with -fno-split-stack to avoid a linker error
avoid the inability to call from split-stack code to non-split-stack
code.

Change-Id: I2afcaf355ed242d40c0bb77bd32faa795e79faea

Reviewed-on: https://go-review.googlesource.com/14598
Reviewed-by: Ian Lance Taylor <ia...@golang.org>

---
M libgo/Makefile.am
M libgo/Makefile.in
M libgo/configure
M libgo/configure.ac
M libgo/testsuite/Makefile.in
5 files changed, 23 insertions(+), 4 deletions(-)

Approvals:
Ian Lance Taylor: Looks good to me, approved