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

$ go version
go version go1.14.2 windows/amd64

Does this issue reproduce with the latest release?

Yes

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

$ go env
set GO111MODULE=
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\XXX\AppData\Local\go-build
set GOENV=C:\Users\XXX\AppData\Roaming\go\env
set GOEXE=.exe
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=C:\Users\XXX\go
set GOPRIVATE=
set GOPROXY=https://proxy.golang.org,direct
set GOROOT=c:\go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=c:\go\pkg\tool\windows_amd64
set GCCGO=gccgo
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=1
set GOMOD=C:\Users\XXX\go\src\github.com\pierrec\tmp\go.mod
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -mthreads -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\XXX\AppData\Local\Temp\go-build610762850=/tmp/go-build -gno-record-gcc-switches

What did you do?

See issue pierrec/lz4#77

What did you expect to see?

A successful build.

What did you see instead?

go: finding module for package github.com/pierrec/lz4/internal/lz4errors
go: finding module for package github.com/pierrec/lz4/internal/lz4block
go: finding module for package github.com/pierrec/lz4/internal/lz4stream
........\pkg\mod\github.com\pierrec\lz4\v4@v4.0.0\lz4.go:14:2: module github.com/pierrec/lz4@latest found (v2.5.2+incompatible), but does not contain package github.com/pierrec/lz4/internal/lz4block
........\pkg\mod\github.com\pierrec\lz4\v4@v4.0.0\lz4.go:15:2: module github.com/pierrec/lz4@latest found (v2.5.2+incompatible), but does not contain package github.com/pierrec/lz4/internal/lz4errors
........\pkg\mod\github.com\pierrec\lz4\v4@v4.0.0\reader.go:7:2: module github.com/pierrec/lz4@latest found (v2.5.2+incompatible), but does not contain package github.com/pierrec/lz4/internal/lz4stream