[clang] [clang] diagnose invalid std::tuple_size sizes (PR #159677)

[Erich Keane via cfe-commits]

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@@ -1222,6 +1222,16 @@ static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
   if (E.isInvalid())
     return IsTupleLike::Error;
 
+  if (Size < 0 || Size >= UINT_MAX) {
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erichkeane wrote:

This test doesn't seem all that right.  I think we should be checking `if (Size.isNegative() || !Size.isSignedIntN(Ctx.getTypeSize(Ctx.getSizeType()))` or something like that like that ?

(should that just be `isIntN`?).

host-compiler `UINT_MAX` is almost definitely the wrong thing here.  


https://github.com/llvm/llvm-project/pull/159677