[compiler-rt] rtsan: Support free_sized and free_aligned_sized from C23 (PR #145085)

[Chris Apple via llvm-commits]

================
@@ -869,6 +869,48 @@ INTERCEPTOR(void, free, void *ptr) {
   return REAL(free)(ptr);
 }
 
+#if SANITIZER_INTERCEPT_FREE_SIZED
+INTERCEPTOR(void, free_sized, void *ptr, SIZE_T size) {
+  if (DlsymAlloc::PointerIsMine(ptr))
+    return DlsymAlloc::Free(ptr);
+
+  // According to the C and C++ standard, freeing a nullptr is guaranteed to be
+  // a no-op (and thus real-time safe). This can be confirmed for looking at
+  // __libc_free in the glibc source.
+  if (ptr != nullptr)
+    __rtsan_notify_intercepted_call("free_sized");
+
+  if (REAL(free_sized))
----------------
cjappl wrote:

Is this something we should do with the rest of our interceptors as well? 

It was my previous understanding that if someone got into this interceptor without a valid REAL version on their system, their binary would likely crash and die (which is acceptable, because they called some illegal function).

https://github.com/llvm/llvm-project/pull/145085