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x/tools/gopls/internal/analysis/yield: another false positive with a reified boolean #76803

@PaulForgey

Description

@PaulForgey
Details ### gopls version
Build info
----------
golang.org/x/tools/gopls v0.20.0
    golang.org/x/tools/gopls@v0.20.0 h1:fxOYZXKl6IsOTKIh6IgjDbIDHlr5btOtOUkrGOgFDB4=
    github.com/BurntSushi/toml@v1.5.0 h1:W5quZX/G/csjUnuI8SUYlsHs9M38FC7znL0lIO+DvMg=
    github.com/fatih/camelcase@v1.0.0 h1:hxNvNX/xYBp0ovncs8WyWZrOrpBNub/JfaMvbURyft8=
    github.com/fatih/gomodifytags@v1.17.1-0.20250423142747-f3939df9aa3c h1:dDSgAjoOMp8da3egfz0t2S+t8RGOpEmEXZubcGuc0Bg=
    github.com/fatih/structtag@v1.2.0 h1:/OdNE99OxoI/PqaW/SuSK9uxxT3f/tcSZgon/ssNSx4=
    github.com/fsnotify/fsnotify@v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
    github.com/google/go-cmp@v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
    golang.org/x/exp/typeparams@v0.0.0-20250620022241-b7579e27df2b h1:KdrhdYPDUvJTvrDK9gdjfFd6JTk8vA1WJoldYSi0kHo=
    golang.org/x/mod@v0.26.0 h1:EGMPT//Ezu+ylkCijjPc+f4Aih7sZvaAr+O3EHBxvZg=
    golang.org/x/sync@v0.16.0 h1:ycBJEhp9p4vXvUZNszeOq0kGTPghopOL8q0fq3vstxw=
    golang.org/x/sys@v0.34.0 h1:H5Y5sJ2L2JRdyv7ROF1he/lPdvFsd0mJHFw2ThKHxLA=
    golang.org/x/telemetry@v0.0.0-20250710130107-8d8967aff50b h1:DU+gwOBXU+6bO0sEyO7o/NeMlxZxCZEvI7v+J4a1zRQ=
    golang.org/x/text@v0.27.0 h1:4fGWRpyh641NLlecmyl4LOe6yDdfaYNrGb2zdfo4JV4=
    golang.org/x/tools@v0.35.1-0.20250728180453-01a3475a31bc h1:ZRKyKRJl/YEWl9ScZwd6Ua6xSt7DE6tHp1I3ucMroGM=
    golang.org/x/vuln@v1.1.4 h1:Ju8QsuyhX3Hk8ma3CesTbO8vfJD9EvUBgHvkxHBzj0I=
    honnef.co/go/tools@v0.7.0-0.dev.0.20250523013057-bbc2f4dd71ea h1:fj8r9irJSpolAGUdZBxJIRY3lLc4jH2Dt4lwnWyWwpw=
    mvdan.cc/gofumpt@v0.8.0 h1:nZUCeC2ViFaerTcYKstMmfysj6uhQrA2vJe+2vwGU6k=
    mvdan.cc/xurls/v2@v2.6.0 h1:3NTZpeTxYVWNSokW3MKeyVkz/j7uYXYiMtXRUfmjbgI=
go: go1.25.3

go env

AR='ar'
CC='clang'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='clang++'
GCCGO='gccgo'
GO111MODULE=''
GOARCH='arm64'
GOARM64='v8.0'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/Users/paulforgey/Library/Caches/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/Users/paulforgey/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/qx/slmgntl158g0mb9zs8hgnwx00000gn/T/go-build3805868096=/tmp/go-build -gno-record-gcc-switches -fno-common'
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMOD='/Users/paulforgey/src/filter/go.mod'
GOMODCACHE='/Users/paulforgey/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/paulforgey/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/Users/paulforgey/Library/Application Support/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.25.3'
GOWORK=''
PKG_CONFIG='pkg-config'

What did you do?

https://go.dev/play/p/b8vUV2lrSMO

func xiter() iter.Seq[int] {
	return func(yield func(int) bool) {
		ok := true
		for i := range 3 {
			if ok {
				ok = yield(i) // yield may be called again after returning false
			}
		}
	}
}

simple program that will falsely trip the yield checker. Granted, this pattern seems a bit strange, but there's quite a bit more going on in the actual code where I found this.

What did you see happen?

yield may be called again after returning false

What did you expect to see?

no warning

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    BugReportIssues describing a possible bug in the Go implementation.ToolsThis label describes issues relating to any tools in the x/tools repository.goplsIssues related to the Go language server, gopls.

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