[clang] [Clang] strengthen checks for 'main' function to meet [basic.start.main] p2 requirements (PR #101853)

[via cfe-commits]

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@@ -3292,11 +3292,9 @@ bool FunctionDecl::isImmediateFunction() const {
 }
 
 bool FunctionDecl::isMain() const {
-  const TranslationUnitDecl *tunit =
-    dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
-  return tunit &&
-         !tunit->getASTContext().getLangOpts().Freestanding &&
-         isNamed(this, "main");
+  const DeclContext *DC = getDeclContext();
+  return isNamed(this, "main") && !getLangOpts().Freestanding &&
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Sirraide wrote:

I don’t see how they couldn’t be the same seeing as `Decl`’s `getLangOpts()` just gets them from the `ASTContext` either way. I think this change is fine.

https://github.com/llvm/llvm-project/pull/101853