[clang] [Clang] Allow vanilla C function symbol name to be used in __attribute__((alias)) when -funique-internal-linkage-names is specified (PR #145652)

[Eli Friedman via cfe-commits]

================
@@ -598,6 +599,23 @@ static bool checkAliasedGlobal(
     return false;
   }
 
+  // Only resolve unique internal linkage symbols for C code
+  if (!CGM->getLangOpts().CPlusPlus) {
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efriedma-quic wrote:

Is this C-only?  Consider something like:

```
long bar(const struct A*p) __attribute__((__alias__("foo")));
namespace {
extern "C" long foo(const struct A*p) {return 1;}
}
```

https://github.com/llvm/llvm-project/pull/145652