From 6c041c54bc710cf818afd630f31161ce0352ebcd Mon Sep 17 00:00:00 2001
From: ths <ths@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Sun, 18 Mar 2007 23:23:31 +0000
Subject: [PATCH] Disable compiler options dangerous for op compilation.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2495 c046a42c-6fe2-441c-8c8c-71466251a162
---
 Makefile.target | 27 ++++++++++++++++-----------
 configure       |  8 --------
 2 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/Makefile.target b/Makefile.target
index c0a79f9699..38899ff14f 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -70,16 +70,26 @@ BASE_LDFLAGS+=-static
 endif
 
 # We require -O2 to avoid the stack setup prologue in EXIT_TB
-OP_CFLAGS = -Wall -O2 -g -fno-strict-aliasing
+OP_CFLAGS := -Wall -O2 -g -fno-strict-aliasing
+
+# cc-option
+# Usage: OP_CFLAGS+=$(call cc-option, -falign-functions=0, -malign-functions=0)
+
+cc-option = $(shell if $(CC) $(OP_CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
+              > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+
+OP_CFLAGS+=$(call cc-option, -fno-reorder-blocks, "")
+OP_CFLAGS+=$(call cc-option, -fno-gcse, "")
+OP_CFLAGS+=$(call cc-option, -fno-tree-ch, "")
+OP_CFLAGS+=$(call cc-option, -fno-optimize-sibling-calls, "")
+OP_CFLAGS+=$(call cc-option, -fno-crossjumping, "")
+OP_CFLAGS+=$(call cc-option, -fno-align-labels, "")
+OP_CFLAGS+=$(call cc-option, -fno-align-jumps, "")
+OP_CFLAGS+=$(call cc-option, -fno-align-functions, $(call cc-option, -malign-functions=0, ""))
 
 ifeq ($(ARCH),i386)
 HELPER_CFLAGS+=-fomit-frame-pointer
 OP_CFLAGS+=-mpreferred-stack-boundary=2 -fomit-frame-pointer
-ifeq ($(HAVE_GCC3_OPTIONS),yes)
-OP_CFLAGS+= -falign-functions=0 -fno-gcse
-else
-OP_CFLAGS+= -malign-functions=0
-endif
 ifdef TARGET_GPROF
 USE_I386_LD=y
 endif
@@ -163,11 +173,6 @@ ifeq ($(ARCH),mips)
 BASE_LDFLAGS+=-Wl,-T,$(SRC_PATH)/$(ARCH).ld
 endif
 
-ifeq ($(HAVE_GCC3_OPTIONS),yes)
-# very important to generate a return at the end of every operation
-OP_CFLAGS+=-fno-reorder-blocks -fno-optimize-sibling-calls
-endif
-
 ifeq ($(CONFIG_DARWIN),yes)
 LIBS+=-lmx
 endif
diff --git a/configure b/configure
index 515d1f38ec..d64fd04be9 100755
--- a/configure
+++ b/configure
@@ -475,11 +475,6 @@ int main(void) {
 }
 EOF
 
-have_gcc3_options="no"
-if $cc -fno-reorder-blocks -fno-optimize-sibling-calls -o $TMPO $TMPC 2> /dev/null ; then
-   have_gcc3_options="yes"
-fi
-
 ##########################################
 # SDL probe
 
@@ -654,9 +649,6 @@ echo "#define CONFIG_QEMU_SHAREDIR \"$prefix$datasuffix\"" >> $config_h
 echo "MAKE=$make" >> $config_mak
 echo "INSTALL=$install" >> $config_mak
 echo "CC=$cc" >> $config_mak
-if test "$have_gcc3_options" = "yes" ; then
-  echo "HAVE_GCC3_OPTIONS=yes" >> $config_mak
-fi
 echo "HOST_CC=$host_cc" >> $config_mak
 echo "AR=$ar" >> $config_mak
 echo "STRIP=$strip -s -R .comment -R .note" >> $config_mak
-- 
2.11.0