make: Re-generate %.texi if HEAD changed since previous run

3 files changed, 7 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index d9f1c87..c2ac7de 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,7 @@
 /docs/*.info
 /docs/*.pdf
 /docs/*.texi
+/docs/.revdesc
 /docs/dir
 /docs/stats/
 /lisp/*-autoloads.el
diff --git a/default.mk b/default.mk
index f152f45..0577715 100644
--- a/default.mk
+++ b/default.mk
@@ -12,6 +12,7 @@ DOMAIN      ?= magit.vc
 CFRONT_DIST ?= E2LUHBKU1FBV02
 
 VERSION ?= $(shell test -e $(TOP).git && git describe --tags --abbrev=0 | cut -c2-)
+REVDESC := $(shell test -e $(TOP).git && git describe --tags)
 
 EMACS      ?= emacs
 EMACS_ARGS ?=
diff --git a/docs/Makefile b/docs/Makefile
index 7a39da8..4285014 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -18,7 +18,11 @@ redo-docs:
 	@touch $(PKG).org
 	@make docs
 
-%.texi: %.org
+.revdesc: ;
+_    := $(shell test "$(REVDESC)" = "$$(cat .revdesc 2> /dev/null)" ||\
+        echo "$(REVDESC)" > .revdesc)
+
+%.texi: %.org .revdesc
 	@printf "Generating $@\n"
 	@$(EMACS) $(ORG_ARGS) $< $(ORG_EVAL)