[clang] [clang-tools-extra] [lldb] [clang] implement CWG1980 and CWG2064: instantiation-dependency improvements (PR #190495)

[Oliver Hunt via cfe-commits]

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@@ -167,8 +167,7 @@ class TemplateArgument {
     unsigned Kind : 31;
     LLVM_PREFERRED_TYPE(bool)
     unsigned IsDefaulted : 1;
-    LLVM_PREFERRED_TYPE(bool)
-    unsigned IsCanonicalExpr : 1;
+    unsigned ExprCanonKind : 2;
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ojhunt wrote:

please add `LLVM_PREFERRED_TYPE(CanonicalizationKind)`, both for debugging and diagnostics (I made our bitfield enum diagnostics reason about preferred type if it's an enum :)

https://github.com/llvm/llvm-project/pull/190495