Makefile: Calculate $(GOROOT), etc. relative to Makefile instead of using $(PWD), which is not always available (eg., in debuild).

Makefile

@@ -66,10 +66,10 @@ config:
 	$(MAKE) -C config
 
 $(SELFLINK): $(GOPATH)
-	ln -s $(CURDIR) $@
+	ln -s $(MAKEFILE_DIR) $@
 
 $(GOPATH):
-	cp -a $(CURDIR)/Godeps/_workspace $(GOPATH)
+	cp -a $(MAKEFILE_DIR)/Godeps/_workspace $(GOPATH)
 
 dependencies: $(GOCC) | $(SELFLINK)
 

Makefile.INCLUDE

@@ -24,7 +24,9 @@ ARCH=$(shell uname -m)
 # Mac OS X release family.
 MAC_OS_X_VERSION ?= 10.8
 
-BUILD_PATH = $(PWD)/.build
+MAKEFILE_DIR ?= $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
+
+BUILD_PATH = $(MAKEFILE_DIR)/.build
 
 GO_VERSION := 1.4
 GOOS = $(subst Darwin,darwin,$(subst Linux,linux,$(subst FreeBSD,freebsd,$(OS))))