build: avoid autogen on 'make clean'

Tested by running 'git submodule foreach git pull origin master' and
'git add .gnulib', then seeing that 'make clean' skips autogen
although 'make' properly runs it.

* cfg.mk (_clean_requested): New check, to speed up 'make clean'
even if gnulib submodule is outdated.
Suggested by Daniel P. Berrange.

diff --git a/cfg.mk b/cfg.mk
index 70465c3b5a3b6c3810bae6acbb1497c8bad6851d..f422a53e2e5afad011d1e86c1687a0009c796f67 100644 (file)
--- a/cfg.mk
+++ b/cfg.mk
@@ -301,7 +301,8 @@ ifeq (0,$(MAKELEVEL))
                git diff .gnulib);                                      \
       stamp="$$($(_submodule_hash) $(_curr_status) 2>/dev/null)";      \
       test "$$stamp" = "$$actual"; echo $$?)
-  ifeq (1,$(_update_required))
+  _clean_requested = $(filter %clean,$(MAKECMDGOALS))
+  ifeq (1,$(_update_required)$(_clean_requested))
     $(info INFO: gnulib update required; running ./autogen.sh first)
 Makefile: _autogen
   endif