release/19.x: Forward declare OSSpinLockLock on MacOS since it's not shipped on the system. (#101392)

[llvmbot]

Backport 3a4c7cc

Requested by: @aemerson

[llvmbot]

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: None (llvmbot)

Changes

Backport 3a4c7cc

Requested by: @aemerson

---

Full diff: https://github.com/llvm/llvm-project/pull/101432.diff

1 Files Affected:

• (modified) compiler-rt/lib/rtsan/rtsan_interceptors.cpp (+12)

diff --git a/compiler-rt/lib/rtsan/rtsan_interceptors.cpp b/compiler-rt/lib/rtsan/rtsan_interceptors.cpp
index 4d5423ec629d2..b63040446e53c 100644
--- a/compiler-rt/lib/rtsan/rtsan_interceptors.cpp
+++ b/compiler-rt/lib/rtsan/rtsan_interceptors.cpp
@@ -21,6 +21,18 @@
 #include "rtsan/rtsan_context.h"
 
 #if SANITIZER_APPLE
+
+#if TARGET_OS_MAC
+// On MacOS OSSpinLockLock is deprecated and no longer present in the headers,
+// but the symbol still exists on the system. Forward declare here so we
+// don't get compilation errors.
+#include <stdint.h>
+extern "C" {
+typedef int32_t OSSpinLock;
+void OSSpinLockLock(volatile OSSpinLock *__lock);
+}
+#endif
+
 #include <libkern/OSAtomic.h>
 #include <os/lock.h>
 #endif

[TNorthover]

Looks safe enough to me. The added declaration matches the one in the header. I don't think it's actually gone yet in the latest Xcode 16 beta public SDK, but presumably it's happening soon.

[github-actions]

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