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Why is #golang now a non-deterministic language with the 1.27 FMA changes? Pure Go code producing different output on different platforms. Avoiding that is why I *moved* to Go.

Jake Bailey

@jakebailey.dev

18 Sept

I assume you mean go.dev/cl/799984 and go.dev/cl/801620; these kinds of changes I think have always been allowed go.dev/ref/spec#:~:... You can use pkg.go.dev/golang.org/x... with -compile=fma to sus out issues, I think, or GOCOMPILEDEBUG=fmahash=...

pkg.go.devbisect command - golang.org/x/tools/cmd/bisect - Go Packages

Jake Bailey

@jakebailey.dev

This made me wonder if any code I maintain has FMA bugs and yep... So now I'm making a lint rule for TS's repo that bans it entirely

18/9/26, 5:37 pm0 reposts0 likes

Jake Bailey

@jakebailey.dev

18 Sept

Yep, fun github.com/microsoft/Ty...

github.comBan implicit floating-point FMAs by jakebailey · Pull Request #64323 · microsoft/TypeScriptInspired by recent Go compression bugs with Go 1.27 doing more FMA on ARM, I had copilot write a lint rule to go through our repo and find anything that might be a bug. The lint rule (and GOCOMPILE...