From 36968546e5d3835b4d3d2f0a0a4f8b0632eb9003 Mon Sep 17 00:00:00 2001
From: Jim Meyering <jim@meyering.net>
Date: Tue, 27 Apr 2004 14:57:33 +0000
Subject: [PATCH] (sc_src_functions_have_static_scope): New rule.

---
 src/Makefile.am | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/Makefile.am b/src/Makefile.am
index 61e05b51b8..8356f1430f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -270,3 +270,22 @@ s2 = '/^\#define AUTHORS \\\\/{;n;$(sed_filter);p;q;}'
 	  done | $(ASSORT) -u ) > $@-t
 	chmod a-w $@-t
 	mv $@-t $@
+
+# The following rule is not designed to be portable,
+# and relies on tools that not everyone has.
+
+# Most functions in src/*.c should have static scope.
+# Any that don't must be marked with `extern', but `main'
+# and `usage' are exceptions.  They're always extern, but
+# don't need to be marked.
+sc_src_functions_have_static_scope: $(all_programs)
+	@t=exceptions-$$$$;						\
+	trap "s=$$?; rm -f $$t; exit $$s" 0 1 2 13 15;			\
+	( printf '^main$$\n^usage$$\n';					\
+	  grep -h -A1 '^extern .*[^;]$$' $(SOURCES)			\
+	    | grep -vE '^(extern |--)' |sed 's/^/^/;s/ .*/$$/' ) > $$t;	\
+	nm -e *.$(OBJEXT)						\
+	    | sed -n 's/.* T //p'					\
+	    | grep -Ev -f $$t &&					\
+	  { echo 'the above functions should have static scope' 1>&2;	\
+	    exit 1; } || :
-- 
2.47.3