From e0d9b73207bd3e41c175042216839974db10d07a Mon Sep 17 00:00:00 2001 From: Collin Funk Date: Fri, 7 Feb 2025 21:21:05 -0800 Subject: [PATCH] gh-129838: Don't redefine _Py_NO_SANITIZE_UNDEFINED Newer GCC versions accept both __attribute__((no_sanitize("undefined"))) and __attribute__((no_sanitize_undefined)) so check that the macro is not already defined. --- .../Build/2025-02-07-21-20-21.gh-issue-129838.fkuiEc.rst | 2 ++ Modules/faulthandler.c | 9 +++++---- 2 files changed, 7 insertions(+), 4 deletions(-) create mode 100644 Misc/NEWS.d/next/Build/2025-02-07-21-20-21.gh-issue-129838.fkuiEc.rst diff --git a/Misc/NEWS.d/next/Build/2025-02-07-21-20-21.gh-issue-129838.fkuiEc.rst b/Misc/NEWS.d/next/Build/2025-02-07-21-20-21.gh-issue-129838.fkuiEc.rst new file mode 100644 index 00000000000000..958460249a65b6 --- /dev/null +++ b/Misc/NEWS.d/next/Build/2025-02-07-21-20-21.gh-issue-129838.fkuiEc.rst @@ -0,0 +1,2 @@ +Don't redefine ``_Py_NO_SANITIZE_UNDEFINED`` when compiling with a recent +GCC version and undefined sanitizer enabled. diff --git a/Modules/faulthandler.c b/Modules/faulthandler.c index a15ced22677ab7..4bfb63e66d2b62 100644 --- a/Modules/faulthandler.c +++ b/Modules/faulthandler.c @@ -37,14 +37,15 @@ #define PUTS(fd, str) (void)_Py_write_noraise(fd, str, strlen(str)) -// clang uses __attribute__((no_sanitize("undefined"))) -// GCC 4.9+ uses __attribute__((no_sanitize_undefined)) -#if defined(__has_feature) // Clang +// Clang and GCC 9.0+ use __attribute__((no_sanitize("undefined"))) +#if defined(__has_feature) # if __has_feature(undefined_behavior_sanitizer) # define _Py_NO_SANITIZE_UNDEFINED __attribute__((no_sanitize("undefined"))) # endif #endif -#if defined(__GNUC__) \ + +// GCC 4.9+ uses __attribute__((no_sanitize_undefined)) +#if !defined(_Py_NO_SANITIZE_UNDEFINED) && defined(__GNUC__) \ && ((__GNUC__ >= 5) || (__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) # define _Py_NO_SANITIZE_UNDEFINED __attribute__((no_sanitize_undefined)) #endif