[compiler-rt] [compiler-rt][ASan] Define SANITIZER_INTERCEPT_WCSNLEN (PR #164845)

[Zack Johnson via llvm-commits]

https://github.com/zacklj89 created https://github.com/llvm/llvm-project/pull/164845

Follow up to #162028

`SANITIZER_INTERCEPT_WCSNLEN` is not defined, so `internal_wcsnlen` is always used instead of using `REAL(wcsnlen)` if intercepted. 

>From 43530cc69241fd7a594b9f5c4d9b67647d7a9217 Mon Sep 17 00:00:00 2001
From: Zack Johnson <zajohnson at microsoft.com>
Date: Thu, 23 Oct 2025 12:27:47 -0400
Subject: [PATCH] Define SANITIZER_WCSNLEN

---
 .../lib/sanitizer_common/sanitizer_platform_interceptors.h       | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
index 88ecd7e16306a..ed60671014d5a 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
@@ -551,6 +551,7 @@ SANITIZER_WEAK_IMPORT void *aligned_alloc(__sanitizer::usize __alignment,
 #define SANITIZER_INTERCEPT_MALLOC_USABLE_SIZE (!SI_MAC && !SI_NETBSD)
 #define SANITIZER_INTERCEPT_MCHECK_MPROBE SI_LINUX_NOT_ANDROID
 #define SANITIZER_INTERCEPT_WCSLEN 1
+#define SANITIZER_INTERCEPT_WCSNLEN 1
 #define SANITIZER_INTERCEPT_WCSCAT (SI_POSIX || SI_WINDOWS)
 #define SANITIZER_INTERCEPT_WCSDUP SI_POSIX
 #define SANITIZER_INTERCEPT_SIGNAL_AND_SIGACTION (!SI_WINDOWS && SI_NOT_FUCHSIA)