From 126552d49e6cba09ef5a504ee3fcdfec00d8743b Mon Sep 17 00:00:00 2001
From: Richard Kreckel <kreckel@ginac.de>
Date: Mon, 15 Aug 2005 21:19:16 +0000
Subject: [PATCH] * m4/cc.m4 (CL_AS_NOEXECSTACK): New macro... * configure.ac:
 ...used here for setting ASMFLAGS... * src/Makefile.in: ...which are used
 here.

---
 ChangeLog       |  6 ++++++
 configure.ac    |  2 ++
 m4/cc.m4        | 27 +++++++++++++++++++++++++++
 src/Makefile.in |  4 ++--
 4 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 299a542..1d33bd0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2005-08-15  Richard B. Kreckel  <kreckel@ginac.de>
+
+	* m4/cc.m4 (CL_AS_NOEXECSTACK): New macro...
+	* configure.ac: ...used here for setting ASMFLAGS...
+	* src/Makefile.in: ...which are used here.
+
 2005-08-02  Andreas Jochens  <aj@andaco.de>
 
 	* include/cln/config.h.in: Add support for PowerPC 64 CPU.
diff --git a/configure.ac b/configure.ac
index bd77b6d..6020485 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,6 +51,8 @@ AC_PROG_CXXCPP
                       dnl sets variable CXXCPP
 CL_AS_UNDERSCORE
                       dnl sets variable AS_UNDERSCORE, DEFS ASM_UNDERSCORE
+CL_AS_NOEXECSTACK
+                      dnl sets variable ASMFLAGS
 AC_PROG_RANLIB
                       dnl sets variable RANLIB
 AC_PROG_INSTALL
diff --git a/m4/cc.m4 b/m4/cc.m4
index 9a8326c..ec6c5e8 100644
--- a/m4/cc.m4
+++ b/m4/cc.m4
@@ -40,3 +40,30 @@ if test "$ac_compiler_gnu" = yes; then
   fi
 fi
 ])
+
+
+dnl Checks whether the stack can be marked nonexecutable by passing an option
+dnl to the C-compiler when acting on .s files. Appends that option to ASFLAGS.
+dnl This macro is adapted from one found in GLIBC-2.3.5.
+AC_DEFUN([CL_AS_NOEXECSTACK],[
+AC_REQUIRE([AC_PROG_CC])
+AC_CACHE_CHECK([whether --noexecstack is desirable for .s files], cl_cv_as_noexecstack, [dnl
+  cat > conftest.c <<EOF
+void foo() {}
+EOF
+  if AC_TRY_COMMAND([${CC} $CFLAGS $CPPFLAGS
+                     -S -o conftest.s conftest.c >/dev/null]) \
+     && grep -q .note.GNU-stack conftest.s \
+     && AC_TRY_COMMAND([${CC} $CFLAGS $CPPFLAGS -Wa,--noexecstack
+                       -c -o conftest.o conftest.s >/dev/null])
+  then
+    cl_cv_as_noexecstack=yes
+  else
+    cl_cv_as_noexecstack=no
+  fi
+  rm -f conftest*])
+  if test "$cl_cv_as_noexecstack" = yes; then
+    ASMFLAGS="$ASMFLAGS -Wa,--noexecstack"
+  fi
+  AC_SUBST(ASMFLAGS)
+])
diff --git a/src/Makefile.in b/src/Makefile.in
index 885f27f..bb786be 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -122,7 +122,7 @@ alls : $(FILES_S) $(ASMFILES_S)
 
 allo : $(FILES_LO) $(ASMFILES_LO)
 
-ASMFLAGS :=
+ASMFLAGS := @ASMFLAGS@
 ifeq (@AS_UNDERSCORE@,true)
 ASMFLAGS += -DUNDERSCORE
 endif
@@ -185,7 +185,7 @@ $(ASMFILES_LO) : %.lo : %.s
 	|| COMPILER_PATH=/bin $(LIBTOOL_COMPILE) $(CC) $(CFLAGS) $(TARGET_ARCH) -c $<
 else
 $(ASMFILES_LO) : %.lo : %.s
-	$(LIBTOOL_COMPILE) $(CC) $(CFLAGS) $(TARGET_ARCH) -c $<
+	$(LIBTOOL_COMPILE) $(CC) $(CFLAGS) $(ASMFLAGS) $(TARGET_ARCH) -c $<
 endif
 
 endif