PWD is set by the shell, not make, and might not match. For example, this broke the build through Homebrew, because PWD stays at the directory where brew is ran.
@@ -26,7 +26,7 @@ LINUX_HEADERS_SITE = http://ftp.barfooze.de/pub/sabotage/tarballs/
DL_CMD = wget -c -O
-COWPATCH = $(PWD)/cowpatch.sh
+COWPATCH = $(CURDIR)/cowpatch.sh
HOST = $(if $(NATIVE),$(TARGET))
BUILD_DIR = build/$(if $(HOST),$(HOST),local)/$(TARGET)
Filippo Valsorda