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

[Reid Kleckner via cfe-commits]

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

If this is only needed from files in src/, can the file be moved out of libcxx/include into libcxx/src? I see .h files in there, but I'm not sure what the proper conventions are these days.

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