[PATCH 1/1] build: write VERSION file containing $(VERSION) string

[Tomi Ollila <tomi.ollila@iki.fi>]

This version file will be as prerequisite to the target files
that use the version info for some purpose, like printing
it to the user to examine. The contents of the VERSION file
is seldom read by the build system itself as the $(VERSION)
variable has the same information.
---
 Makefile.local | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Makefile.local b/Makefile.local
index c85e09c..1f876b3 100644
--- a/Makefile.local
+++ b/Makefile.local
@@ -22,6 +22,8 @@ VERSION:=$(shell cat ${srcdir}/version)
 ifeq ($(filter release release-message pre-release update-versions,$(MAKECMDGOALS)),)
 ifeq ($(IS_GIT),yes)
 VERSION:=$(shell git describe --match '[0-9.]*'|sed -e s/_/~/ -e s/-/+/ -e s/-/~/)
+# Make the 'VERSION' file depend *also* on .git/HEAD in this case
+VERSION: .git/HEAD
 endif
 endif
 
@@ -69,6 +71,11 @@ ifeq ($(shell cat .first-build-message 2>/dev/null),)
 endif
 endif
 
+# This VERSION file is used mostly for triggering other file remakes...
+# This may get other dependency to .git/HEAD above in this file.
+VERSION: version
+	echo $(VERSION) > $@
+
 $(TAR_FILE):
 	if git tag -v $(VERSION) >/dev/null 2>&1; then \
            ref=$(VERSION); \
@@ -280,6 +287,8 @@ notmuch_client_srcs =		\
 
 notmuch_client_modules = $(notmuch_client_srcs:.c=.o)
 
+notmuch.o: VERSION
+
 notmuch: $(notmuch_client_modules) lib/libnotmuch.a util/libutil.a parse-time-string/libparse-time-string.a
 	$(call quiet,CXX $(CFLAGS)) $^ $(FINAL_LIBNOTMUCH_LDFLAGS) -o $@
 
@@ -318,7 +327,7 @@ install-desktop:
 	desktop-file-install --mode 0644 --dir "$(DESTDIR)$(desktop_dir)" notmuch.desktop
 
 SRCS  := $(SRCS) $(notmuch_client_srcs)
-CLEAN := $(CLEAN) notmuch notmuch-shared $(notmuch_client_modules) notmuch.elc
+CLEAN := $(CLEAN) VERSION notmuch notmuch-shared $(notmuch_client_modules)
 
 DISTCLEAN := $(DISTCLEAN) .first-build-message Makefile.config
 
-- 
1.8.5.3