Support recovery from C stack overflow on MS-Windows

* src/w32fns.c (w32_reset_stack_overflow_guard)
(stack_overflow_handler): New functions for handling C stack
overflow exceptions.
(my_exception_handler): Handle EXCEPTION_STACK_OVERFLOW exceptions
specially, and zero out except_addr if we do.
(globals_of_w32fns): Initialize dwMainThreadId in non-interactive
mode.
* src/sysdep.c [HAVE_STACK_OVERFLOW_HANDLING]: Add !WINDOWSNT to
the condition, as HAVE_STACK_OVERFLOW_HANDLING is now defined for
the MinGW build, but the code guarded by that is for Posix hosts.
* src/keyboard.c (command_loop) [WINDOWSNT]: Call
w32_reset_stack_overflow_guard.

* nt/inc/ms-w32.h (sigjmp_buf): New typedef.
(sigsetjmp): New macro.
(w32_reset_stack_overflow_guard): Declare the prototype.

* configure.ac (HAVE_STACK_OVERFLOW_HANDLING): Set to 1 for MinGW.

1 files changed, 5 insertions, 1 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index 5f8667586c4..e4fe5b9bb4c 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1092,7 +1092,11 @@ command_loop (void)
   /* At least on GNU/Linux, saving signal mask is important here.  */
   if (sigsetjmp (return_to_command_loop, 1) != 0)
     {
-      /* Comes here from handle_sigsegv, see sysdep.c.  */
+      /* Comes here from handle_sigsegv (see sysdep.c) and
+         stack_overflow_handler (see w32fns.c).  */
+#ifdef WINDOWSNT
+      w32_reset_stack_overflow_guard ();
+#endif
       init_eval ();
       Vinternal__top_level_message = recover_top_level_message;
     }