[clang] [clang] Don't use `VarDecl` of local variables as `ManglingContextDecl` for lambdas (PR #179035)

[Corentin Jabot via cfe-commits]

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In-Reply-To: <llvm.org/llvm/llvm-project/pull/179035 at github.com>


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@@ -287,32 +273,33 @@ Sema::getCurrentMangleNumberContext(const DeclContext *DC) {
     DataMember,
     InlineVariable,
     TemplatedVariable,
+    ExternallyVisibleVariableInModulePurview,
     Concept,
-    NonInlineInModulePurview
   } Kind = Normal;
 
   bool IsInNonspecializedTemplate =
       inTemplateInstantiation() || CurContext->isDependentContext();
 
+  // Checks if a VarDecl or FunctionDecl is from a module purview and externally
+  // visible. These Decls should be treated as "inline" for the purpose of
+  // mangling in the code below.
+  //
+  // See discussion in https://github.com/itanium-cxx-abi/cxx-abi/issues/186
+  //
+  // zygoloid:
+  //    Yeah, I think the only cases left where lambdas don't need a
+  //    mangling are when they have (effectively) internal linkage or
+  //    appear in a non-inline function in a non-module translation unit.
----------------
cor3ntin wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/179035