On Thu, Feb 23, 2023 at 10:14:13PM +0000, Jamie Landeg-Jones wrote: ! Peter <p...@citylink.dinoex.sub.org> wrote: ! ! > -target-cpu westmere ! > ! > But when building with CPTYPE?=native, the code works! ! ! That's weird!
Ah. Hm... ! I notice the only difference between those 2 is that the "native" one ! specifically sets (-target-feature +...) or unsets (-target-feature -...) ! the features to use. ! ! Presumably there is something enabled by default that shouldn't be ! (for westmere), but the extra flags added with "native" fix that. Very likely so. ! This is more a question for the clang folks, but if you're really ! interested, you could try (on your -march=westmere build) ! disabling them in ever decreasing group sizes until you narrow ! down the culprit! Negative. I have a whole lot more of these little nasty bugs to pursue. Bug number is 269792 Cheerio, and kind thanks for the helping hand!
