[clang] [clang] Reject array comparisons in C++26 for unknown/dependent types in templates (PR #191101)

[via cfe-commits]

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@@ -12488,8 +12488,7 @@ static void diagnoseTautologicalComparison(Sema &S, SourceLocation Loc,
   QualType LHSType = LHS->getType();
   QualType RHSType = RHS->getType();
   if (LHSType->hasFloatingRepresentation() ||
-      (LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)) ||
-      S.inTemplateInstantiation())
+      (LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)))
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Sirraide wrote:

> That check makes sense if all we’re doing is emitting tautological comparison warnings

Also, this means that in older language modes where these comparisons aren’t deprecated, the tautological comparison warning (but _not_ the deprecation warning or error) should continue to be guarded behind `inTemplateInstantiation()`

https://github.com/llvm/llvm-project/pull/191101