Patch #1350409: Port signal handling to VS 2005.

Misc/ACKS

@@ -113,6 +113,7 @@ David Chaum
 Nicolas Chauvat
 Michael Chermside
 Albert Chin-A-Young
+Adal Chiriliuc
 Tom Christiansen
 Vadim Chugunov
 David Cinege

Misc/NEWS

@@ -12,6 +12,8 @@ What's New in Python 2.5 alpha 1?
 Core and builtins
 -----------------
 
+- Patch #1350409: Work around signal handling bug in Visual Studio 2005.
+
 - Bug #1281408: Py_BuildValue now works correct even with unsigned longs
   and long longs.
 

Python/pythonrun.c

@@ -1615,6 +1615,23 @@ PyOS_getsig(int sig)
 	return context.sa_handler;
 #else
 	PyOS_sighandler_t handler;
+/* Special signal handling for the secure CRT in Visual Studio 2005 */
+#if defined(_MSC_VER) && _MSC_VER >= 1400
+	switch (sig) {
+	/* Only these signals are valid */
+	case SIGINT:
+	case SIGILL:
+	case SIGFPE:
+	case SIGSEGV:
+	case SIGTERM:
+	case SIGBREAK:
+	case SIGABRT:
+		break;
+	/* Don't call signal() with other values or it will assert */
+	default:
+		return SIG_ERR;
+	}
+#endif /* _MSC_VER && _MSC_VER >= 1400 */
 	handler = signal(sig, SIG_IGN);
 	if (handler != SIG_ERR)
 		signal(sig, handler);