Bug#12096

  "Add line for non-executable stack in .s files"
  Fix so that configure will use "--noexecstack" for assembler if gcc supports
  option and compiled C doesn't need executable stack.


config/ac-macros/compiler_flag.m4:
  Bug#12096
    Add macro to check if "--noexecstack" should be used when compiling assembler
configure.in:
  Bug#12096
    Add macro to check if "--noexecstack" should be used when compiling assembler
strings/Makefile.am:
  Bug#12096
    Automake knows how to handle assembler

config/ac-macros/compiler_flag.m4

@@ -38,3 +38,25 @@ AC_DEFUN([AC_SYS_OS_COMPILER_FLAG],
  fi
 ])
 
+AC_DEFUN([AC_CHECK_NOEXECSTACK],
+[
+ AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
+		mysql_cv_as_noexecstack, [dnl
+  cat > conftest.c <<EOF
+void foo (void) { }
+EOF
+  if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
+		     -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
+     && grep -q .note.GNU-stack conftest.s \
+     && AC_TRY_COMMAND([${CC-cc} $CCASFLAGS $CPPFLAGS -Wa,--noexecstack
+		       -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
+  then
+    mysql_cv_as_noexecstack=yes
+  else
+    mysql_cv_as_noexecstack=no
+  fi
+  rm -f conftest*])
+ if test $mysql_cv_as_noexecstack = yes; then
+   CCASFLAGS="$CCASFLAGS -Wa,--noexecstack"
+ fi
+])

configure.in

@@ -515,6 +515,10 @@ AM_PROG_CC_STDC
 
 # We need an assembler, too
 AM_PROG_AS
+CCASFLAGS="$CCASFLAGS $ASFLAGS"
+
+# Check if we need noexec stack for assembler
+AC_CHECK_NOEXECSTACK
 
 if test "$am_cv_prog_cc_stdc" = "no"
 then

strings/Makefile.am

@@ -66,12 +66,6 @@ conf_to_src_LDFLAGS= @NOINST_LDFLAGS@
 #strtoull.o:		@CHARSET_OBJS@
 
 
-if ASSEMBLER
-# On Linux gcc can compile the assembly files
-%.o	: %.s
-	$(AS) $(ASFLAGS) -o $@ $<
-endif
-
 FLAGS=$(DEFS) $(INCLUDES) $(CPPFLAGS) $(CFLAGS) @NOINST_LDFLAGS@
 
 str_test: str_test.c $(pkglib_LIBRARIES)