Can't build with "-race" (but only sometimes)

[stnokott]

For some reason, compiling my application (and any example from this repo) with -race causes the following error during compilation:

$ go run -race ./examples/helloworld/helloworld.go
# command-line-arguments
panic: inlined function github.com/AllenDang/cimgui-go/internal.ReinterpretCast[*github.com/AllenDang/cimgui-go/imgui._Ctype_struct_ImGuiIO,go.shape.*uint8] missing func info

Full error

$ go run -race ./examples/helloworld/helloworld.go
# command-line-arguments
panic: inlined function github.com/AllenDang/cimgui-go/internal.ReinterpretCast[*github.com/AllenDang/cimgui-go/imgui._Ctype_struct_ImGuiIO,go.shape.*uint8] missing func info

goroutine 1 [running]:
cmd/link/internal/ld.genInlTreeSym(0xc0001b0000, 0x4?, {0xc000124008, 0xc00018a180, {0x79f86480ffdf, 0x70, 0x70}, {0x4, 0x14, 0x3, ...}}, ...)
        cmd/link/internal/ld/pcln.go:212 +0x4b9
cmd/link/internal/ld.makeInlSyms(0xc0001b0000, {0xc003e98a00, 0x1430, 0x1430?}, 0xc00007adb0)
        cmd/link/internal/ld/pcln.go:235 +0x21e
cmd/link/internal/ld.(*Link).pclntab(0xc0001b0000, {0xc0040c4000?, 0xc00019a090?, 0x16?})
        cmd/link/internal/ld/pcln.go:839 +0x1ce
cmd/link/internal/ld.Main(_, {0x20, 0x20, 0x1, 0x7, 0x10, 0x0, {0xc000010441, 0x1, 0x1}, ...})
        cmd/link/internal/ld/main.go:430 +0x185c
main.main()
        cmd/link/main.go:72 +0xddb

Compiling with -gcflags='github.com/AllenDang/cimgui-go/...=-l' causes the error to go away.

Note that I only have this issue on one of my Windows hosts on a WSL Ubuntu for some reason (works on WSL Ubuntu on a different host), so it might not even be a giu/cimgui-go issue, but I am still at my wit's end so I'd be happy for any ideas on what could be the root cause.

---

Additional information if needed

Things I tried without success:

• up-/downgrading Go version
• up-/downgrading Go toolchain version
• compiling with -extldflags=-static

go env

AR='ar'
CC='cc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='c++'
GCCGO='gccgo'
GO111MODULE=''
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/home/stnokott/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/home/stnokott/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3737892945=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/dev/null'
GOMODCACHE='/home/stnokott/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/stnokott/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/home/linuxbrew/.linuxbrew/Cellar/go/1.25.0/libexec'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/home/stnokott/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/home/linuxbrew/.linuxbrew/Cellar/go/1.25.0/libexec/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.25.0'
GOWORK=''
PKG_CONFIG='pkg-config'

[gucio321]

tbh, thats the stranges go panic I've ever seen...
and I can't find anything about it (well I've searched something about 1 min but still...)
maybe this is somehow related to generics? (this ReiterpretCast is used quite often in the code) - thats only my guess. this could be anything

[gucio321]

@stnokott check this: golang/go#73947

[stnokott]

Wow thanks for the quick reply!
Honestly very strange to me too since I have pretty much identical software setups on my two machines, but only have the issue on one of their WSL OS...

Since you haven't seen this before either, I reckon it's not a giu/cimgui issue then. I'll follow the issue you linked for now. Maybe I'll also fork cimgui and add a //go:noinline, see if that helps find the root cause.

Thanks anyways!