[clang] [clang][Interp] Integral pointers (PR #84159)

[Aaron Ballman via cfe-commits]

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@@ -53,6 +57,10 @@ class FunctionPointer final {
     return toAPValue().getAsString(Ctx, Func->getDecl()->getType());
   }
 
+  uint32_t getIntegerRepresentation() const {
+    return static_cast<uint32_t>(reinterpret_cast<uintptr_t>(Func));
+  }
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AaronBallman wrote:

This seems dangerous to me. `Func` is a pointer, so casting to `uintptr_t` makes sense, but then casting to a 32-bit value seems likely to cause problems due to truncation. Any reason why this shouldn't return a `uintptr_t`?

https://github.com/llvm/llvm-project/pull/84159