Default to stack objects on DOS_NT platforms as well.

 src/w32term.h (ALIGN_STACK) [__GNUC__]: Define to
 __attribute__((force_align_arg_pointer)) for GCC 4.2 and later.
 src/lisp.h (USE_STACK_LISP_OBJECTS): Remove the !DOS_NT condition.
 src/w32proc.c (enum_locale_fn, enum_codepage_fn): Add the
 ALIGN_STACK attribute.
 src/w32fns.c (w32_monitor_enum): Add the ALIGN_STACK attribute.
 src/w32uniscribe.c (add_opentype_font_name_to_list): Add the
 ALIGN_STACK attribute.
 src/w32font.c (add_font_name_to_list, add_font_entity_to_list)
 (add_one_font_entity_to_list): Add the ALIGN_STACK attribute.

1 files changed, 16 insertions, 0 deletions

diff --git a/src/w32term.h b/src/w32term.h
index 0fabe12819c..fcadca6a9af 100644
--- a/src/w32term.h
+++ b/src/w32term.h
@@ -22,6 +22,22 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "frame.h"
 #include "atimer.h"
 
+/* Stack alignment stuff.  Every CALLBACK function should have the
+   ALIGN_STACK attribute if it manipulates Lisp objects, because
+   Windows x86 32-bit ABI only guarantees 4-byte stack alignment, and
+   that is what we will get when a Windows function calls us.  The
+   ALIGN_STACK attribute forces GCC to emit a preamble code to
+   re-align the stack at function entry.  Further details about this
+   can be found in http://www.peterstock.co.uk/games/mingw_sse/.  */
+#ifdef __GNUC__
+# if defined USE_STACK_LISP_OBJECTS && defined _W64     \
+  && __GNUC__ + (__GNUC_MINOR__ > 1) >= 5
+#  define ALIGN_STACK __attribute__((force_align_arg_pointer))
+# else
+#  define ALIGN_STACK
+# endif  /* USE_STACK_LISP_OBJECTS */
+#endif
+
 
 #define BLACK_PIX_DEFAULT(f) PALETTERGB(0,0,0)
 #define WHITE_PIX_DEFAULT(f) PALETTERGB(255,255,255)