cmd/compile: //go:build file version ignored when calling generic fn which has related type params (reproduces with 1.21 and 1.20, not at tip) #64759
Description
Go version
go version go1.21.5 darwin/amd64
What operating system and processor architecture are you using (go env)?
GO111MODULE=''
GOARCH='amd64'
GOBIN=''
GOCACHE='/Users/corysnider/Library/Caches/go-build'
GOENV='/Users/corysnider/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMODCACHE='/Volumes/Workspace/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Volumes/Workspace'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/Cellar/go/1.21.5/libexec'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/Cellar/go/1.21.5/libexec/pkg/tool/darwin_amd64'
GOVCS=''
GOVERSION='go1.21.5'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='cc'
CXX='c++'
CGO_ENABLED='1'
GOMOD='/dev/null'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/8p/tzn5bkn967vfgttpr2d2kpjm0000gq/T/go-build2320458225=/tmp/go-build -gno-record-gcc-switches -fno-common'What did you do?
$ cat repro.go
//go:build go1.18
package repro
func genericfn[S ~[]E, E any](s S) S {
return s
}
func do() []string {
return genericfn([]string{})
}
$ go tool compile -lang=go1.16 repro.goWhat did you expect to see?
Compilation succeeds. It succeeds with go version devel go1.22-b60bf8f8e1 Fri Dec 15 19:35:21 2023 +0000 darwin/amd64.
What did you see instead?
embedding interface element ~[]string requires go1.18 or later (-lang was set to go1.16; check go.mod)