From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun, 7 Sep 2025 23:34:43 +0000 (-0700)
Subject: maint: allow false/true in C macros
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d041f83c60240db782663908da219fc1144915f;p=thirdparty%2Fgnulib.git

maint: allow false/true in C macros

* top/maint.mk (sc_Wundef_boolean): Allow false and true in C
macro definiens.  C23 requires support for false and true, and the
‘bool’ module makes it easy to support this in older compilers.
---

diff --git a/ChangeLog b/ChangeLog
index 2ff90ef8b7..0c132816f4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2025-09-07  Paul Eggert  <eggert@cs.ucla.edu>
+
+	maint: allow false/true in C macros
+	* top/maint.mk (sc_Wundef_boolean): Allow false and true in C
+	macro definiens.  C23 requires support for false and true, and the
+	‘bool’ module makes it easy to support this in older compilers.
+
 2025-09-07  Bruno Haible  <bruno@clisp.org>
 
 	bootstrap: Improve efficiency of "git clone".
diff --git a/top/maint.mk b/top/maint.mk
index e03e887cba..1a6511b4f8 100644
--- a/top/maint.mk
+++ b/top/maint.mk
@@ -1454,10 +1454,13 @@ sc_prohibit_reversed_compare_failure:
 # That would be flagged by using -Wundef, however gnulib currently
 # tests many undefined macros, and so we can't enable that option.
 # So at least preclude common boolean strings as macro values.
+# Although this rule formerly also complained about 'true' and 'false',
+# that complaint is now incorrect given that C23 has blessed this practice
+# and the 'bool' module supports it.
 sc_Wundef_boolean:
-	@prohibit='^#define.*(yes|no|true|false)$$'			\
+	@prohibit='^#define.*(yes|no)$$'				\
 	in_files='$(CONFIG_INCLUDE)'					\
-	halt='Use 0 or 1 for macro values'				\
+	halt='Use 0/1 or false/true for macro values'			\
 	  $(_sc_search_regexp)
 
 # Even if you use pathmax.h to guarantee that PATH_MAX is defined, it might