MaskRay wrote: > > > @MaskRay Are you OK with this change? > > > > > > Sorry for the delay. I've read through > > [discourse.llvm.org/t/making-ffp-model-fast-more-user-friendly/78402](https://discourse.llvm.org/t/making-ffp-model-fast-more-user-friendly/78402), > > how we ended up with `-ffp-contract=fast-honor-pragmas` beside `=fast` > > (GCC compatibility, sigh), some notes that ICC/GCC have behavior > > differences. A different, safer mode for `-ffp-model` (absent from GCC) > > makes sense to me. > > GCC doesn't support the pragma, and ICC doesn't have a mode that only allows > contraction within a single expression (as the C standard requires), so I > don't think compatibility with the behavior of the pragma in those compilers > makes sense. > > I personally feel very strongly that even our -ffast-math handling should > honor pragmas by default and that -ffp-contract=fast should honor pragmas > (perhaps with the addition of -ffp-contract=fast-no-honor-pragmas if anyone > really needs that). Someone else was surprised by this behavior earlier this > year (#88633). On the other hand, we've got a bug in the front end where we > crash with "#pragma STDC FP_CONTRACT DEFAULT" if you've used > "-ffp-contract=fast-honor-pragmas" > ([godbolt.org/z/EqE6Kn6Wf](https://godbolt.org/z/EqE6Kn6Wf)) so maybe I > should hold the fp-contract change back for a future patch.
I've read https://discourse.llvm.org/t/fp-contract-fast-and-pragmas/58529 and I agree that `fast`/`fast-honor-pragmas` could be merged and if needed, `-fast-no-honor-pragmas` could be added (I suspect that there is no such need...) https://github.com/llvm/llvm-project/pull/100453 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
