[clang] [Clang] Ignore invalid base classes (PR #147213)

[Corentin Jabot via cfe-commits]

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@@ -2252,7 +2252,7 @@ void Parser::ParseBaseClause(Decl *ClassDecl) {
   while (true) {
     // Parse a base-specifier.
     BaseResult Result = ParseBaseSpecifier(ClassDecl);
-    if (Result.isInvalid()) {
+    if (!Result.isUsable()) {
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cor3ntin wrote:

Result can either be invalid, null, or valid - this changes what we do in the null case, ie we don't want null base classes - does that make sense? 

https://github.com/llvm/llvm-project/pull/147213