On Thu, 2 Jul 2026, Richard Biener via Gcc wrote: > > Am 02.07.2026 um 18:22 schrieb Joseph Myers via Gcc <[email protected]>: > > > > On Thu, 2 Jul 2026, Richard Biener via Gcc wrote: > > > >> Maybe -ffp-exceptions={none,ieee,ieee-alternate}? > > > > Both ieee and ieee-alternate would encompass a wide range of restrictions > > on permitted transformations (adding exceptions, losing exceptions, moving > > where exceptions occur, etc.) that it's not clear should be grouped > > together like that. > > It would be easy to understand because it were to use standards terms? > But do you have an alternative suggestion? I specifically wanted a way > to exclude alternate exception handling methods like traps because that > simplifies EH
I don't have a specific suggestion for naming, but the relevant subdivisions of ieee (less clear it's useful to subdivide ieee-alternate) are the ones discussed earlier in this thread. The full semantics of ieee would go well beyond what the existing -ftrapping-math implements, since while -ftrapping-math might do reasonably well at avoiding adding extra exceptions, it's weaker at avoiding removing exceptions that should be raised in the abstract machine (will remove code whose results seem to be unused, I think) and doesn't really try at all to avoid moving floating-point code past function calls or asms that might test / modify exception flags. -- Joseph S. Myers [email protected]
