[glibc] stdio-common: Silence clang -Wfortify-source warning in tst-vfscanf-bz34008

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=d9981b54396038bb85f3b2db7b68de1f6755530b

commit d9981b54396038bb85f3b2db7b68de1f6755530b
Author: Adhemerval Zanella <[email protected]>
Date:   Fri May 15 11:07:26 2026 -0300

    stdio-common: Silence clang -Wfortify-source warning in tst-vfscanf-bz34008
    
    clang does not recognize the 'm' scanf specifier and incorrectly warns
    that the buf argument may overflow.  Suppress the warning with the
    clang-specific DIAG_* macros.

Diff:
---
 stdio-common/tst-vfscanf-bz34008.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/stdio-common/tst-vfscanf-bz34008.c b/stdio-common/tst-vfscanf-bz34008.c
index 48371c8a3d..ebf7ec3e4c 100644
--- a/stdio-common/tst-vfscanf-bz34008.c
+++ b/stdio-common/tst-vfscanf-bz34008.c
@@ -24,6 +24,7 @@
 #include <stdlib.h>
 #include <malloc.h>
 #include <support/check.h>
+#include <libc-diag.h>
 
 #define WIDTH 0x410
 #define SCANFSTR "%1040mc"
@@ -37,7 +38,14 @@ do_test (void)
   input[WIDTH] = '\0';
 
   char *buf = NULL;
+
+  /* clang does not recognize the 'm' scanf specifier and incorrectly warns
+     that the buf argument may overflow ((argument 3 has size 8, but the
+     corresponding specifier may require size 1040).  */
+  DIAG_PUSH_NEEDS_COMMENT_CLANG;
+  DIAG_IGNORE_NEEDS_COMMENT_CLANG (18, "-Wfortify-source");
   TEST_VERIFY (sscanf (input, SCANFSTR, &buf) != -1);
+  DIAG_POP_NEEDS_COMMENT_CLANG;
   TEST_VERIFY (buf != NULL);
 
   free (buf);