Incorrect typecheck "imported but not used" finding

[djm-google]

Welcome

• Yes, I'm using a binary release within 2 latest major releases. Only such installations are supported.
• Yes, I've searched similar issues on GitHub and didn't find any.
• Yes, I've included all information below (version, config, etc.).
• Yes, I've tried with the standalone linter if available (e.g., gocritic, go vet, etc.). (https://golangci-lint.run/usage/linters/)

Description of the problem

The typecheck linter reports an unused import in the google/go-attestation package, but the import is definitely used in the file that has the report:

$ git clone --quiet https://github.com/google/go-attestation
$ cd go-attestation/
$ golangci-lint run
attest/attest-tool/attest-tool.go:6:2: "crypto/ecdsa" imported but not used (typecheck)
	"crypto/ecdsa"
	^
$ grep -1 -n ecdsa attest/attest-tool/attest-tool.go
5-	"bytes"
6:	"crypto/ecdsa"
7-	"crypto/rand"
--
246-	switch pub := ek.Public.(type) {
247:	case *ecdsa.PublicKey:
248-		data, err := x509.MarshalPKIXPublicKey(pub)

There are build tags used elsewhere in this module, but not in this file (referencing issue #3891). Running go mod tidy doesn't help (referencing issue #2133).

I see this in the Github action (example) and when running locally.

Any suggestions?

Version of golangci-lint

$ golangci-lint --version
golangci-lint has version 1.53.3 built with go1.20.5 from 2dcd82f3 on 2023-06-15T10:50:11Z

Configuration file

$ cat .golangci.yml
cat: .golangci.yml: No such file or directory
$ cat ~/.golangci.yml
cat: /home/djm/.golangci.yml: No such file or directory

Go environment

$ go version && go env
go version go1.19.10 linux/amd64
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/djm/.cache/go-build"
GOENV="/home/djm/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/djm/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/djm/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="go1.19.10"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/djm/go-attestation/go.mod"
GOWORK=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build1936490003=/tmp/go-build -gno-record-gcc-switches"

Verbose output of running

$ golangci-lint cache clean
$ golangci-lint run -v
INFO [config_reader] Config search paths: [./ /home/djm/go-attestation /home/djm /home /] 
INFO [config_reader] Used config file .golangci.yaml 
INFO [lintersdb] Active 7 linters: [gofmt gosimple govet ineffassign staticcheck typecheck unused] 
INFO [loader] Go packages loading at mode 575 (imports|types_sizes|compiled_files|deps|files|exports_file|name) took 276.470587ms 
INFO [runner/filename_unadjuster] Pre-built 0 adjustments in 20.677462ms 
INFO [linters_context/goanalysis] analyzers took 9.196922321s with top 10 stages: buildir: 7.305555419s, inspect: 610.145462ms, ctrlflow: 215.382642ms, printf: 189.421728ms, fact_purity: 149.638463ms, fact_deprecated: 141.105395ms, SA5012: 133.237886ms, nilness: 99.744016ms, typedness: 69.333115ms, S1039: 32.049188ms 
INFO [runner] Issues before processing: 142, after processing: 1 
INFO [runner] Processors filtering stat (out/in): severity-rules: 1/1, filename_unadjuster: 142/142, path_prettifier: 142/142, nolint: 141/141, max_from_linter: 1/1, sort_results: 1/1, cgo: 142/142, exclude: 142/142, max_same_issues: 1/1, fixer: 1/1, path_shortener: 1/1, path_prefixer: 1/1, autogenerated_exclude: 142/142, exclude-rules: 141/142, uniq_by_line: 1/141, source_code: 1/1, max_per_file_from_linter: 1/1, skip_files: 142/142, skip_dirs: 142/142, identifier_marker: 142/142, diff: 1/1 
INFO [runner] processing took 6.049552ms with stages: identifier_marker: 2.433569ms, exclude-rules: 2.243738ms, nolint: 808.425µs, autogenerated_exclude: 184.451µs, path_prettifier: 164.861µs, skip_dirs: 119.881µs, source_code: 50.662µs, cgo: 12.523µs, uniq_by_line: 11.257µs, filename_unadjuster: 10.052µs, max_same_issues: 2.551µs, max_from_linter: 1.99µs, path_shortener: 1.756µs, skip_files: 1.023µs, max_per_file_from_linter: 746ns, severity-rules: 555ns, exclude: 447ns, sort_results: 342ns, fixer: 314ns, diff: 284ns, path_prefixer: 125ns 
INFO [runner] linters took 4.132309074s with stages: goanalysis_metalinter: 4.126110896s 
attest/attest-tool/attest-tool.go:6:2: "crypto/ecdsa" imported and not used (typecheck)
	"crypto/ecdsa"
	^
INFO File cache stats: 1 entries of total size 7.8KiB 
INFO Memory: 46 samples, avg is 183.0MB, max is 248.4MB 
INFO Execution took 4.439548611s     

Code example or link to a public repository

https://github.com/google/go-attestation

[boring-cyborg]

Hey, thank you for opening your first Issue ! 🙂 If you would like to contribute we have a guide for contributors.

[ldez]

Hello,

You are using go1.19 locally and in your CI but the project sets go1.20 in its go.mod.

go1.20

$ docker run --rm -it golang:1.20-alpine sh
/go # apk add git curl
fetch https://dl-cdn.alpinelinux.org/alpine/v3.17/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/v3.17/community/x86_64/APKINDEX.tar.gz
(1/7) Installing brotli-libs (1.0.9-r9)
(2/7) Installing nghttp2-libs (1.51.0-r0)
(3/7) Installing libcurl (8.1.2-r0)
(4/7) Installing curl (8.1.2-r0)
(5/7) Installing libexpat (2.5.0-r0)
(6/7) Installing pcre2 (10.42-r0)
(7/7) Installing git (2.38.5-r0)
Executing busybox-1.35.0-r29.trigger
OK: 16 MiB in 23 packages
/go # curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.53.3
golangci/golangci-lint info checking GitHub for tag 'v1.53.3'
golangci/golangci-lint info found version: 1.53.3 for v1.53.3/linux/amd64
golangci/golangci-lint info installed /go/bin/golangci-lint
/go # git clone --quiet https://github.com/google/go-attestation
/go # cd go-attestation/
/go/go-attestation # golangci-lint run -v
INFO [config_reader] Config search paths: [./ /go/go-attestation /go / /root]
INFO [config_reader] Used config file .golangci.yaml
INFO [lintersdb] Active 7 linters: [gofmt gosimple govet ineffassign staticcheck typecheck unused]
INFO [loader] Go packages loading at mode 575 (exports_file|imports|types_sizes|compiled_files|deps|files|name) took 3.400675401s
INFO [runner/filename_unadjuster] Pre-built 0 adjustments in 6.68849ms
INFO [linters_context/goanalysis] analyzers took 3.129663811s with top 10 stages: buildir: 2.084247687s, inspect: 106.394397ms, printf: 58.111377ms, ctrlflow: 56.16251ms, gofmt: 51.700404ms, fact_deprecated: 49.937577ms, fact_purity: 47.73155ms, SA5012: 43.385057ms, S1038: 42.139872ms, nilness: 39.672569ms
INFO [runner] Issues before processing: 1, after processing: 0
INFO [runner] Processors filtering stat (out/in): autogenerated_exclude: 1/1, exclude: 1/1, exclude-rules: 0/1, identifier_marker: 1/1, skip_files: 1/1, cgo: 1/1, filename_unadjuster: 1/1, path_prettifier: 1/1, skip_dirs: 1/1
INFO [runner] processing took 96.535µs with stages: autogenerated_exclude: 28.105µs, identifier_marker: 24.048µs, exclude-rules: 13.604µs, skip_dirs: 13.56µs, path_prettifier: 12.16µs, cgo: 976ns, nolint: 565ns, max_same_issues: 492ns, diff: 474ns, filename_unadjuster: 422ns, skip_files: 328ns, fixer: 307ns, source_code: 281ns, uniq_by_line: 263ns, exclude: 191ns, severity-rules: 190ns, path_shortener: 170ns, max_from_linter: 137ns, sort_results: 109ns, max_per_file_from_linter: 82ns, path_prefixer: 71ns
INFO [runner] linters took 990.624893ms with stages: goanalysis_metalinter: 990.483942ms
INFO File cache stats: 0 entries of total size 0B
INFO Memory: 46 samples, avg is 76.8MB, max is 269.5MB
INFO Execution took 4.401110727s                  
/go/go-attestation # go build ./...
/go/go-attestation #

go1.19

$ docker run --rm -it golang:1.19-alpine sh
/go # apk add git curl
fetch https://dl-cdn.alpinelinux.org/alpine/v3.16/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/v3.16/community/x86_64/APKINDEX.tar.gz
(1/7) Installing brotli-libs (1.0.9-r6)
(2/7) Installing nghttp2-libs (1.47.0-r0)
(3/7) Installing libcurl (8.1.2-r0)
(4/7) Installing curl (8.1.2-r0)
(5/7) Installing expat (2.5.0-r0)
(6/7) Installing pcre2 (10.40-r0)
(7/7) Installing git (2.36.6-r0)
Executing busybox-1.35.0-r17.trigger
OK: 20 MiB in 22 packages
/go # curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.53.3
golangci/golangci-lint info checking GitHub for tag 'v1.53.3'
golangci/golangci-lint info found version: 1.53.3 for v1.53.3/linux/amd64
golangci/golangci-lint info installed /go/bin/golangci-lint
/go # git clone --quiet https://github.com/google/go-attestation
/go # cd go-attestation/
/go/go-attestation # golangci-lint run -v
INFO [config_reader] Config search paths: [./ /go/go-attestation /go / /root] 
INFO [config_reader] Used config file .golangci.yaml 
INFO [lintersdb] Active 7 linters: [gofmt gosimple govet ineffassign staticcheck typecheck unused] 
INFO [loader] Go packages loading at mode 575 (types_sizes|compiled_files|files|name|deps|exports_file|imports) took 1.801918445s 
INFO [runner/filename_unadjuster] Pre-built 0 adjustments in 7.154419ms 
INFO [linters_context/goanalysis] analyzers took 1.980360834s with top 10 stages: buildir: 1.427504661s, inspect: 86.960384ms, ctrlflow: 51.102549ms, fact_purity: 47.180505ms, printf: 46.705053ms, fact_deprecated: 44.659417ms, SA5012: 42.670369ms, nilness: 36.978ms, typedness: 34.93439ms, gofmt: 4.282696ms 
INFO [runner] Issues before processing: 291, after processing: 3 
INFO [runner] Processors filtering stat (out/in): uniq_by_line: 3/291, max_per_file_from_linter: 3/3, severity-rules: 3/3, filename_unadjuster: 291/291, path_prettifier: 291/291, autogenerated_exclude: 291/291, path_prefixer: 3/3, skip_dirs: 291/291, source_code: 3/3, path_shortener: 3/3, max_same_issues: 3/3, max_from_linter: 3/3, fixer: 3/3, identifier_marker: 291/291, nolint: 291/291, diff: 3/3, exclude-rules: 291/291, sort_results: 3/3, cgo: 291/291, skip_files: 291/291, exclude: 291/291 
INFO [runner] processing took 5.267985ms with stages: identifier_marker: 2.299534ms, exclude-rules: 2.282836ms, nolint: 496.967µs, path_prettifier: 93.415µs, skip_dirs: 34.231µs, source_code: 29.079µs, cgo: 7.812µs, uniq_by_line: 7.523µs, filename_unadjuster: 5.816µs, autogenerated_exclude: 5.78µs, max_same_issues: 1.888µs, path_shortener: 827ns, max_from_linter: 547ns, max_per_file_from_linter: 469ns, skip_files: 272ns, exclude: 266ns, fixer: 193ns, severity-rules: 177ns, diff: 177ns, sort_results: 100ns, path_prefixer: 76ns 
INFO [runner] linters took 824.960401ms with stages: goanalysis_metalinter: 819.641047ms 
attest/attest-tool/attest-tool.go:6:2: "crypto/ecdsa" imported and not used (typecheck)
        "crypto/ecdsa"
        ^
attest/challenge_test.go:6:2: "crypto/rsa" imported and not used (typecheck)
        "crypto/rsa"
        ^
../../usr/local/go/src/runtime/cgo/cgo.go:31:8: could not import C (cgo preprocessing failed) (typecheck)
import "C"
       ^
INFO File cache stats: 3 entries of total size 11.9KiB 
INFO Memory: 28 samples, avg is 90.2MB, max is 265.5MB 
INFO Execution took 2.636876381s                  
/go/go-attestation # 
/go/go-attestation # go build ./...
../pkg/mod/github.com/google/go-tpm@v0.3.4-0.20230613064043-511507721cb1/legacy/tpm2/credactivation/credential_activation.go:23:2: package crypto/ecdh is not in GOROOT (/usr/local/go/src/crypto/ecdh)

FYI, typecheck is not a real linter it's just a way to parse/display "compilation" and linters errors (linter reports are not errors).

To see your problem you can run go build ./...

[ldez]

google/go-attestation#336