[clang] [clang][bytecode] Always check for initialization in RetValue (PR #233189)

[Oliver Hunt via cfe-commits]

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@@ -331,3 +331,18 @@ namespace UnionNoActivate {
   }
   static_assert(g()); // both-error {{constant expression}} both-note {{in call}}
 }
+
+namespace UninitializedMemberFromConsteval {
+  struct A {
+    int x; // both-note {{subobject declared here}}
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ojhunt wrote:

Consider `// #somelabel` and then later at the error site `// both-note@#somelabel {{subject declared here}}`

That's feedback i was given a while ago and I've found it makes it easier to understand diagnostics tests so have generally adopted it across my tests.

https://github.com/llvm/llvm-project/pull/233189