[clang] [CIR] Add basic support for operator new (PR #145802)

[Erich Keane via cfe-commits]

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@@ -66,6 +66,16 @@ struct CIRGenTypeCache {
     unsigned char PointerSizeInBytes;
   };
 
+  /// The size and alignment of size_t.
+  union {
+    unsigned char SizeSizeInBytes; // sizeof(size_t)
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erichkeane wrote:

Is this used?  Also, fact that this and the one above are unions is odd, right?  Do we ONLY need pointer OR alignment?

https://github.com/llvm/llvm-project/pull/145802