From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Fri, 17 Oct 2025 19:13:01 +0000 (-0300)
Subject: stdio: Fix -Wtautological-constant-out-of-range-compare on clang
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ca3e2f12af1d1272ea05b27dd06660aeaea03f21;p=thirdparty%2Fglibc.git

stdio: Fix -Wtautological-constant-out-of-range-compare on clang

clang emits an error while building vfprintf-internal for default
case:

error: result of comparison of constant 255 with expression of type
'char' is always true
[-Werror,-Wtautological-constant-out-of-range-compare]
          if (spec <= UCHAR_MAX

The test is indeed not required for default non-wide build.

Reviewed-by: Collin Funk <collin.funk1@gmail.com>
---

diff --git a/stdio-common/vfprintf-internal.c b/stdio-common/vfprintf-internal.c
index fa41e1b242..2238137d6d 100644
--- a/stdio-common/vfprintf-internal.c
+++ b/stdio-common/vfprintf-internal.c
@@ -1337,7 +1337,12 @@ printf_positional (struct Xprintf_buffer * buf, const CHAR_T *format,
       /* Process format specifiers.  */
       do
 	{
-	  if (spec <= UCHAR_MAX
+# ifdef COMPILE_WPRINTF
+#  define CHECK_SPEC(spec) ((spec) <= UCHAR_MAX)
+# else
+#  define CHECK_SPEC(spec) (true)
+# endif
+	  if (CHECK_SPEC (spec)
 	      && __printf_function_table != NULL
 	      && __printf_function_table[(size_t) spec] != NULL)
 	    {