Coverage incorrectly reported as 100% ( go test cover)

[vron]

What version of Go are you using (go version)?

go version go1.10.3 darwin/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/vron/Library/Caches/go-build"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/vron/go"
GORACE=""
GOROOT="/usr/local/Cellar/go/1.10.3/libexec"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.10.3/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
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 -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/4m/7vzzk0153d56fs_7b1k4wqdc0000gn/T/go-build593998463=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

For code see: https://play.golang.org/p/mkWebv8IOwK . (not runnable since 3 files needed)

Using the code from the above link and running:
go test -coverpkg="..." -count=1 pkg1/pkg2

Outputs
ok pkg1/pkg2 0.005s coverage: 100.0% of statements in ...

What did you expect to see?

I expect the coverage to not be 100% since pkg1.f1 was never called.

What did you see instead?

I see 100% coverage in all packages, which is clearly wrong.

[AlexRouSg]

Looks like a dupe of #23883

[vron]

Yes, agreed - looks like the same issue - will close this one, unfortunate that it has been pushed to 1.12 since it makes for incorrect reportage without any warnings. Thanks for pointing out the duplicate.