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From: "shaohua.li at inf dot ethz.ch" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug sanitizer/107893] New: gcc trunk at -O0 (UBSan) misses a Null-pointer-dereference Date: Mon, 28 Nov 2022 08:40:18 +0000 [thread overview] Message-ID: <bug-107893-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107893 Bug ID: 107893 Summary: gcc trunk at -O0 (UBSan) misses a Null-pointer-dereference Product: gcc Version: 13.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: sanitizer Assignee: unassigned at gcc dot gnu.org Reporter: shaohua.li at inf dot ethz.ch CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org, jakub at gcc dot gnu.org, kcc at gcc dot gnu.org, marxin at gcc dot gnu.org Target Milestone: --- For the following code, `gcc-trunk -O0 -fsanitize=undefined -fno-sanitize-recover=all` misses the NULL-pointer-dereference, while `gcc-trunk -Ox -fsanitize=address -fno-sanitize-recover=all` (x=1, 2, 3, or s) can detect it. I checked gcc8/9/10/11/12 and they all have this issue. clang can detect it at all optimization levels. Compiler explorer: https://godbolt.org/z/85qfdccse % cat a.c int main() { int *a = 0; (a[1] | a[0]) >> 056; } % % gcc-tk -O0 -fsanitize=undefined -fno-sanitize-recover=all -w a.c &&./a.out Segmentation fault % gcc-tk -O1 -fsanitize=undefined -fno-sanitize-recover=all -w a.c &&./a.out a.c:3:13: runtime error: load of null pointer of type 'int' %
next reply other threads:[~2022-11-28 8:40 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-11-28 8:40 shaohua.li at inf dot ethz.ch [this message] 2022-11-28 8:49 ` [Bug sanitizer/107893] " jakub at gcc dot gnu.org 2022-11-28 8:57 ` rguenth at gcc dot gnu.org 2022-11-28 8:58 ` rguenth at gcc dot gnu.org 2022-11-28 9:05 ` shaohua.li at inf dot ethz.ch
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