[llvm] Unittest for Error forwarding, follow-up to PR #92208 (PR #92314)

[David Blaikie via llvm-commits]

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@@ -1172,6 +1173,7 @@ TEST(Error, ForwardToExpected) {
   };
   std::optional<int> MaybeV;
   EXPECT_THAT_ERROR(ExpectedReturningFct(true).moveInto(MaybeV), Failed());
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dwblaikie wrote:

Huh - how come this existing caller didn't catch the problem already? I thought the issue was that the code didn't compile with the older clang. In which case a fail/success case wouldn't change whether the "does this compile" was exercised, right?

https://github.com/llvm/llvm-project/pull/92314