[Buildroot] [git commit branch/next] package/go: set GOCACHE for download post-process

[Yann E. MORIN]

commit: https://git.buildroot.net/buildroot/commit/?id=07a745e55d76616802a20dcbfd72dfe6fe8e3b05
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/next

The go mod vendor call in support/download/go-post-process accesses the go
cache, so pass GOCACHE= in the environment to ensure our cache directory is
used.

The go cache defaults to ~/.cache/go-build if not set, so this fixes builds
where that location (or GOCACHE if set in the environment) is not writable:

rm -rf ~/.cache/go-build
chmod -w ~/.cache
make docker-compose-source
..
failed to initialize build cache at /home/peko/.cache/go-build: mkdir /home/peko/.cache/go-build: permission denied
make[1]: *** [package/pkg-generic.mk:189: /home/peko/source/buildroot/output/build/docker-compose-2.14.0/.stamp_downloaded] Error 1

We use two different cache directories for target and host builds, but the
download/vendoring should be independent of the architecture, so use the
target variant even for host-only packages for simplicity.

Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998 at free.fr>
---
 package/go/go.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package/go/go.mk b/package/go/go.mk
index d3ed07f03b..c4f72d403c 100644
--- a/package/go/go.mk
+++ b/package/go/go.mk
@@ -25,6 +25,7 @@ HOST_GO_COMMON_ENV = \
 	GOFLAGS=-mod=vendor \
 	GOROOT="$(HOST_GO_ROOT)" \
 	GOPATH="$(HOST_GO_GOPATH)" \
+	GOCACHE="$(HOST_GO_TARGET_CACHE)" \
 	GOPROXY=off \
 	PATH=$(BR_PATH) \
 	GOBIN= \
@@ -75,7 +76,6 @@ HOST_GO_TARGET_ENV = \
 	$(HOST_GO_COMMON_ENV) \
 	GOOS="linux" \
 	GOARCH=$(GO_GOARCH) \
-	GOCACHE="$(HOST_GO_TARGET_CACHE)" \
 	CC="$(TARGET_CC)" \
 	CXX="$(TARGET_CXX)" \
 	CGO_CFLAGS="$(TARGET_CFLAGS)" \