[lld] [libc++] Fix the behavior of throwing `operator new` under -fno-exceptions (PR #69498)

[Louis Dionne via llvm-commits]

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@@ -7,6 +7,8 @@
 //===----------------------------------------------------------------------===//
 
 #include <__memory/aligned_alloc.h>
+#include <__overridable_function>
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ldionne wrote:

So this file needs to be shared between libc++abi and libc++, unfortunately, so it's a bit easier to throw in under `include`.

https://github.com/llvm/llvm-project/pull/69498