From: Bruno Haible <bruno@clisp.org>
Date: Sun, 8 Jun 2025 00:58:21 +0000 (+0200)
Subject: stdcountof-h: Work around a clang bug.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd6bd646350a1bf914701c199194ae4522bb7ca5;p=thirdparty%2Fgnulib.git

stdcountof-h: Work around a clang bug.

Reported by Basil L. Contovounesios <basil@contovou.net> in
<https://lists.gnu.org/archive/html/bug-gnulib/2025-06/msg00073.html>.

* lib/stdcountof.in.h (_gl_verify_is_array): Disable the checking on
clang.
* tests/test-stdcountof-h.c (test_func): Add another test case.
---

diff --git a/ChangeLog b/ChangeLog
index fedd5f6456..ef6c6d19be 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2025-06-07  Bruno Haible  <bruno@clisp.org>
+
+	stdcountof-h: Work around a clang bug.
+	Reported by Basil L. Contovounesios <basil@contovou.net> in
+	<https://lists.gnu.org/archive/html/bug-gnulib/2025-06/msg00073.html>.
+	* lib/stdcountof.in.h (_gl_verify_is_array): Disable the checking on
+	clang.
+	* tests/test-stdcountof-h.c (test_func): Add another test case.
+
 2025-06-06  Collin Funk  <collin.funk1@gmail.com>
 
 	doc: Add some missing Makefile targets.
diff --git a/lib/stdcountof.in.h b/lib/stdcountof.in.h
index 105cf209a5..683b1c7156 100644
--- a/lib/stdcountof.in.h
+++ b/lib/stdcountof.in.h
@@ -81,7 +81,8 @@ template <typename T> _gl_array_type_test<T> _gl_array_type_test_helper(T&);
 # endif
 #else
 /* In C, we can use typeof and __builtin_types_compatible_p.  */
-# if _GL_GNUC_PREREQ (3, 1) || defined __clang__
+/* Work around clang bug <https://github.com/llvm/llvm-project/issues/143284>.  */
+# if _GL_GNUC_PREREQ (3, 1) && ! defined __clang__ /* || defined __clang__ */
 #  define _gl_verify_is_array(a) \
     sizeof (struct { unsigned int _gl_verify_error_if_negative : __builtin_types_compatible_p (typeof (a), typeof (&*(a))) ? -1 : 1; })
 # else
diff --git a/tests/test-stdcountof-h.c b/tests/test-stdcountof-h.c
index cd7e03f331..5d0a9a6611 100644
--- a/tests/test-stdcountof-h.c
+++ b/tests/test-stdcountof-h.c
@@ -58,6 +58,11 @@ test_func (int parameter[3])
   ASSERT (countof (unbounded) >= 0);
 #endif
 
+  {
+    extern int a, b, c;
+    ASSERT (countof (((int[]) { a, b, c })) == 3);
+  }
+
   /* Check that countof(...) is an expression of type size_t.  */
 #if !defined __cplusplus && HAVE__GENERIC
   ASSERT (_Generic (countof (bounded),          size_t: 1, default: 0));