[clang] [clang-repl] Extend the C support. (PR #89804)

[Vassil Vassilev via cfe-commits]

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@@ -407,6 +406,16 @@ void IncrementalParser::CleanUpPTU(PartialTranslationUnit &PTU) {
       }
     }
   }
+
+  // FIXME: We should de-allocate MostRecentTU
+  for (Decl *D : MostRecentTU->decls()) {
+    if (!isa<NamedDecl>(D))
+      continue;
+    // Check if we need to clean up the IdResolver chain.
+    NamedDecl *ND = cast<NamedDecl>(D);
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vgvassilev wrote:

The `isa` + `cast` saves a few instructions in the case where `D` is not a `NamedDecl`. I'd prefer to stay the way it is although we are not expecting a lot of declarations that are not `NamedDecl`s.

https://github.com/llvm/llvm-project/pull/89804