[clang] [libcxx] [libc++][Clang] Updated the diagnostics checks in libc++ tests. (PR #144220)

[Shamshura Egor via cfe-commits]

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@@ -55,6 +55,7 @@ void test() {
       // expected-error-re@*:* {{static assertion failed {{.*}}The result of f(value()) must be a specialization of std::expected}}
       // expected-error-re@*:* {{{{.*}}cannot be used prior to '::' because it has no members}}
       // expected-error-re@*:* {{no matching constructor for initialization of{{.*}}}}
+      // expected-error@*:* {{excess elements in struct initializer}}
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egorshamshura wrote:

This was discussed here: https://github.com/llvm/llvm-project/pull/143309#discussion_r2134728164
As I understand it, this is a temporary solution.

https://github.com/llvm/llvm-project/pull/144220