From: Florian Weimer on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1144#note_598979089 Current GCC compiles this code to use the `msrkc` instruction: ```c #include <stdlib.h> int f (int a, int b) { int result; if (__builtin_mul_overflow (a, b, &result)) abort (); return result; } int main (int argc, char **argv) { return f (atoi (argv[1]), atoi (argv[2])); } ``` Maybe not exactly common, but also not super-obscure. I think the kernel uses `__builtin_mul_overflow` in some places. `s390.md` in GCC has patterns for the other instructions, too, search for `TARGET_Z14`. The sort-of working aspect was the reason why I added the run-time check to glibc. I was worried that without it, some z14 binaries will appear to work, but crash in obscure ways for some operations because GCC happened to emit one of the new instructions. _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
