[llvm] [llvm][Support] Use __NR_gettid on Linux for compat with older glibc (PR #120007)

[Brad Smith via llvm-commits]

https://github.com/brad0 created https://github.com/llvm/llvm-project/pull/120007

None

>From c594784e8dc3eba5de4bafc3de8ce666f6eec79e Mon Sep 17 00:00:00 2001
From: Brad Smith <brad at comstyle.com>
Date: Sun, 15 Dec 2024 10:01:58 -0500
Subject: [PATCH] [llvm][Support] Use __NR_gettid on Linux for compat with
 older glibc

---
 llvm/lib/Support/Unix/Threading.inc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/llvm/lib/Support/Unix/Threading.inc b/llvm/lib/Support/Unix/Threading.inc
index c7b4c7af3b9f33..aedcd9aa34b99a 100644
--- a/llvm/lib/Support/Unix/Threading.inc
+++ b/llvm/lib/Support/Unix/Threading.inc
@@ -141,7 +141,7 @@ uint64_t llvm::get_threadid() {
 #elif defined(__ANDROID__)
   return uint64_t(gettid());
 #elif defined(__linux__)
-  return uint64_t(syscall(SYS_gettid));
+  return uint64_t(syscall(__NR_gettid));
 #else
   return uint64_t(pthread_self());
 #endif