Fix sporadic rebuilds for .pc files

The build of .pc (pkg-config) files depends on all makefiles in use, and
in dependency tracking mode, the previous coding ended up including
/dev/null as a makefile.  Apparently, on some platforms the modification
time of /dev/null changes sporadically, and so the .pc files would end
up being rebuilt every so often.  Fix that by changing the makefile code
to do without using /dev/null.

diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 1077e0b98ab6a07524b7ec9cbb9b56b6104965d1..80f509fa872cc247e37d639ed27f9b3a7cea1e05 100644 (file)
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -687,9 +687,12 @@ ifeq ($(GCC), yes)
 endif # GCC
 
 # Include all the dependency files generated for the current
-# directory. List /dev/null as dummy because if the wildcard expands
-# to nothing then make would complain.
--include $(wildcard $(DEPDIR)/*.Po) /dev/null
+# directory. Note that make would complain if include was called with
+# no arguments.
+Po_files := $(wildcard $(DEPDIR)/*.Po)
+ifneq (,$(Po_files))
+include $(Po_files)
+endif
 
 # hook for clean-up
 clean distclean maintainer-clean: clean-deps