[clang] [clang][Sema] fix crash on __type_pack_element with dependent packs (GH180307) (PR #180407)

[Oliver Hunt via cfe-commits]

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@@ -3416,15 +3420,13 @@ static QualType checkBuiltinTemplateIdType(
     QualType OrigType = Converted[1].getAsType();
     // C++14 [inteseq.intseq]p1:
     //   T shall be an integer type.
-    if (!OrigType->isDependentType() && !OrigType->isIntegralType(Context)) {
+    if (!OrigType->isIntegralType(Context)) {
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ojhunt wrote:

paranoia: add an `assert(!OrigType->isDependentType())` this also makes it more explicit that it is not allowed

https://github.com/llvm/llvm-project/pull/180407