From 4162bc133b21ccb06d3589bd69ddb7bb248c58d2 Mon Sep 17 00:00:00 2001 From: Sam Gross Date: Tue, 11 Mar 2025 10:33:23 -0400 Subject: [PATCH] gh-130396: Fix thread sanitizer crashes on stack overflow tests (gh-130966) Thread sanitizer will often crash if a test uses more than half the stack. --- Python/ceval.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Python/ceval.c b/Python/ceval.c index a702d296e22..f9089d7f11f 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -392,7 +392,12 @@ _Py_InitializeRecursionLimits(PyThreadState *tstate) if (err == 0) { uintptr_t base = ((uintptr_t)stack_addr) + guard_size; _tstate->c_stack_top = base + stack_size; +#ifdef _Py_THREAD_SANITIZER + // Thread sanitizer crashes if we use a bit more than half the stack. + _tstate->c_stack_soft_limit = base + (stack_size / 2); +#else _tstate->c_stack_soft_limit = base + PYOS_STACK_MARGIN_BYTES * 2; +#endif _tstate->c_stack_hard_limit = base + PYOS_STACK_MARGIN_BYTES; assert(_tstate->c_stack_soft_limit < here_addr); assert(here_addr < _tstate->c_stack_top);