bpo-38965: Fix faulthandler._stack_overflow() on GCC 10 (GH-17467)
Use the "volatile" keyword to prevent tail call optimization
on any compiler, rather than relying on compiler specific pragma.
(cherry picked from commit 8b787964e0a647caa0558b7c29ae501470d727d9)
Co-authored-by: Victor Stinner <vstinner@python.org>
diff --git a/Modules/faulthandler.c b/Modules/faulthandler.c
index 251d8e0..230cde4 100644
--- a/Modules/faulthandler.c
+++ b/Modules/faulthandler.c
@@ -1097,18 +1097,14 @@
#if defined(HAVE_SIGALTSTACK) && defined(HAVE_SIGACTION)
#define FAULTHANDLER_STACK_OVERFLOW
-#ifdef __INTEL_COMPILER
- /* Issue #23654: Turn off ICC's tail call optimization for the
- * stack_overflow generator. ICC turns the recursive tail call into
- * a loop. */
-# pragma intel optimization_level 0
-#endif
-static
-uintptr_t
+static uintptr_t
stack_overflow(uintptr_t min_sp, uintptr_t max_sp, size_t *depth)
{
- /* allocate 4096 bytes on the stack at each call */
- unsigned char buffer[4096];
+ /* Allocate (at least) 4096 bytes on the stack at each call.
+
+ bpo-23654, bpo-38965: use volatile keyword to prevent tail call
+ optimization. */
+ volatile unsigned char buffer[4096];
uintptr_t sp = (uintptr_t)&buffer;
*depth += 1;
if (sp < min_sp || max_sp < sp)