maint.mk: new syntax check for HAVE_DECL checks Based on Karel's report, we might as well enforce a syntax check to help avoid future problems. https://lists.gnu.org/archive/html/coreutils/2012-06/msg00037.html Exempt a few files that still get picked up in the wild rather than as a full gnulib module with m4 files. * top/maint.mk (sc_prohibit_defined_have_decl_tests): New rule. * cfg.mk (exclude_file_name_regexp--sc_prohibit_defined_have_decl_tests): Exempt some false positives. Based on a report by Karel Zak. Signed-off-by: Eric Blake <eblake@redhat.com>

--- a/top/maint.mk	Fri Jul 13 11:50:59 2012 -0600
+++ b/top/maint.mk	Fri Jul 13 14:02:05 2012 -0600
@@ -777,6 +777,11 @@
 	'  with the corresponding gnulib module, they are always true')	\
 	  $(_sc_search_regexp)
 
+sc_prohibit_defined_have_decl_tests:
+	prohibit='#[	 ]*if(n?def|.*\<defined)\>[	 (]+HAVE_DECL_'	\
+	halt='$(ME): HAVE_DECL macros are always defined'		\
+	  $(_sc_search_regexp)
+
 # ==================================================================
 gl_other_headers_ ?= \
   intprops.h	\