[clang] [clang] more useful error message for decomposition declaration missing initializer (PR #127924)

[Kevin Bravo via cfe-commits]

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@@ -2933,6 +2933,9 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
   }
   case InitKind::Uninitialized: {
     Actions.ActOnUninitializedDecl(ThisDecl);
+    if (D.isDecompositionDeclarator())
+      Diag(Tok, diag::err_decomp_decl_expected_init)
+          << dyn_cast<VarDecl>(ThisDecl) << PP.getSpelling(Tok);
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kbrav wrote:

It does not. EndLoc is updated when the declaration has mostly finished parsing.

The `Declarator`'s end location is correct though, so the latest commit saves it in the `DecompositionDecl`

https://github.com/llvm/llvm-project/pull/127924