From 07420835d0a4e1220b686e0b7d64394e974fb89b Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Thu, 9 Apr 2020 17:04:55 -0700
Subject: [PATCH] make+build: compile build tags into binary

---
 Makefile         | 18 ++++++++++++------
 build/version.go | 13 +++++++++++++
 2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index d9b05519..9d480601 100644
--- a/Makefile
+++ b/Makefile
@@ -23,8 +23,6 @@ ANDROID_BUILD := $(ANDROID_BUILD_DIR)/Lndmobile.aar
 
 COMMIT := $(shell git describe --abbrev=40 --dirty)
 COMMIT_HASH := $(shell git rev-parse HEAD)
-LDFLAGS := -ldflags "-X $(PKG)/build.Commit=$(COMMIT) \
-	-X $(PKG)/build.CommitHash=$(COMMIT_HASH)"
 
 BTCD_COMMIT := $(shell cat go.mod | \
 		grep $(BTCD_PKG) | \
@@ -53,6 +51,14 @@ include make/testing_flags.mk
 
 DEV_TAGS := $(if ${tags},$(DEV_TAGS) ${tags},$(DEV_TAGS))
 
+make_ldflags = $(shell echo -ldflags \"-X $(PKG)/build.Commit=$(COMMIT) \
+	-X $(PKG)/build.CommitHash=$(COMMIT_HASH) \
+	-X $(PKG)/build.RawTags=$(shell echo $(1) | sed -e 's/ /,/g')\")
+
+LDFLAGS := $(call make_ldflags, ${tags})
+DEV_LDFLAGS := $(call make_ldflags, $(DEV_TAGS))
+ITEST_LDFLAGS := $(call make_ldflags, $(ITEST_TAGS))
+
 # Linting uses a lot of memory, so keep it under control by limiting the number
 # of workers if requested.
 ifneq ($(workers),)
@@ -97,13 +103,13 @@ btcd:
 
 build:
 	@$(call print, "Building debug lnd and lncli.")
-	$(GOBUILD) -tags="$(DEV_TAGS)" -o lnd-debug $(LDFLAGS) $(PKG)/cmd/lnd
-	$(GOBUILD) -tags="$(DEV_TAGS)" -o lncli-debug $(LDFLAGS) $(PKG)/cmd/lncli
+	$(GOBUILD) -tags="$(DEV_TAGS)" -o lnd-debug $(DEV_LDFLAGS) $(PKG)/cmd/lnd
+	$(GOBUILD) -tags="$(DEV_TAGS)" -o lncli-debug $(DEV_LDFLAGS) $(PKG)/cmd/lncli
 
 build-itest:
 	@$(call print, "Building itest lnd and lncli.")
-	$(GOBUILD) -tags="$(ITEST_TAGS)" -o lnd-itest $(LDFLAGS) $(PKG)/cmd/lnd
-	$(GOBUILD) -tags="$(ITEST_TAGS)" -o lncli-itest $(LDFLAGS) $(PKG)/cmd/lncli
+	$(GOBUILD) -tags="$(ITEST_TAGS)" -o lnd-itest $(ITEST_LDFLAGS) $(PKG)/cmd/lnd
+	$(GOBUILD) -tags="$(ITEST_TAGS)" -o lncli-itest $(ITEST_LDFLAGS) $(PKG)/cmd/lncli
 
 install:
 	@$(call print, "Installing lnd and lncli.")
diff --git a/build/version.go b/build/version.go
index 3e3a147f..d863adab 100644
--- a/build/version.go
+++ b/build/version.go
@@ -20,6 +20,10 @@ var (
 	// CommitHash stores the current commit hash of this build, this should
 	// be set using the -ldflags during compilation.
 	CommitHash string
+
+	// RawTags contains the raw set of build tags, separated by commas. This
+	// should be set using -ldflags during compilation.
+	RawTags string
 )
 
 // semanticAlphabet is the set of characters that are permitted for use in an
@@ -74,3 +78,12 @@ func Version() string {
 
 	return version
 }
+
+// Tags returns the list of build tags that were compiled into the executable.
+func Tags() []string {
+	if len(RawTags) == 0 {
+		return nil
+	}
+
+	return strings.Split(RawTags, ",")
+}