From 63a94ad9873cf6837227d29d17b8a4e3d8624e98 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Wed, 4 Oct 2023 15:41:19 -0700
Subject: [PATCH] build: build+install using GOEXPERIMENT=loopvar

We also update the release script to do the same as well.
---
 Makefile           | 14 +++++++++++---
 scripts/release.sh |  6 +++---
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index 6c526f67b..0ed697d4b 100644
--- a/Makefile
+++ b/Makefile
@@ -21,9 +21,17 @@ ANDROID_BUILD := $(ANDROID_BUILD_DIR)/Lndmobile.aar
 
 COMMIT := $(shell git describe --tags --dirty)
 
-GOBUILD := go build -v
-GOINSTALL := go install -v
-GOTEST := GOEXPERIMENT=loopvar go test
+GO_VERSION := $(shell go version | sed -nre 's/^[^0-9]*(([0-9]+\.)*[0-9]+).*/\1/p')
+GO_VERSION_MINOR := $(shell echo $(GO_VERSION) | cut -d. -f2)
+
+LOOPVARFIX :=
+ifeq ($(shell expr $(GO_VERSION_MINOR) \>= 21), 1)
+	LOOPVARFIX := GOEXPERIMENT=loopvar
+endif
+
+GOBUILD := $(LOOPVARFIX) go build -v
+GOINSTALL := $(LOOPVARFIX) go install -v
+GOTEST := $(LOOPVARFIX) go test
 
 GOFILES_NOVENDOR = $(shell find . -type f -name '*.go' -not -path "./vendor/*" -not -name "*pb.go" -not -name "*pb.gw.go" -not -name "*.pb.json.go")
 
diff --git a/scripts/release.sh b/scripts/release.sh
index 930d680e3..0f6b44cff 100755
--- a/scripts/release.sh
+++ b/scripts/release.sh
@@ -98,7 +98,7 @@ function check_tag_correct() {
   fi
 
   # Build lnd to extract version.
-  go build ${PKG}/cmd/lnd
+  env GOEXPERIMENT=loopvar go build ${PKG}/cmd/lnd
 
   # Extract version command output.
   lnd_version_output=$(./lnd --version)
@@ -177,8 +177,8 @@ function build_release() {
     pushd "${dir}"
 
     green " - Building: ${os} ${arch} ${arm} with build tags '${buildtags}'"
-    env CGO_ENABLED=0 GOOS=$os GOARCH=$arch GOARM=$arm go build -v -trimpath -ldflags="${ldflags}" -tags="${buildtags}" ${PKG}/cmd/lnd
-    env CGO_ENABLED=0 GOOS=$os GOARCH=$arch GOARM=$arm go build -v -trimpath -ldflags="${ldflags}" -tags="${buildtags}" ${PKG}/cmd/lncli
+    env GOEXPERIMENT=loopvar CGO_ENABLED=0 GOOS=$os GOARCH=$arch GOARM=$arm go build -v -trimpath -ldflags="${ldflags}" -tags="${buildtags}" ${PKG}/cmd/lnd
+    env GOEXPERIMENT=loopvar CGO_ENABLED=0 GOOS=$os GOARCH=$arch GOARM=$arm go build -v -trimpath -ldflags="${ldflags}" -tags="${buildtags}" ${PKG}/cmd/lncli
     popd
 
     # Add the hashes for the individual binaries as well for easy verification