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Full: Recently, I forgot to include but had included. Due to this recent commit for gcc12 https://github.com/gcc-mirror/gcc/commit/261d5a4a459bd49942e53bc83334ccc7154a09d5 the `error: 'std::array' has incomplete type` felt like a weird regression because all other major gcc versions as well as clang compiled just fine. After many hours of debugging, I finally realised that it was just a missing header and now the error message actually makes sense. But when I experimented with this, I found that gcc does give you another `::: note: declaration of 'class SomeClass'` with line number and everything. Now, I wonder why gcc doesn't do that for standard headers (at least not in my particular case). Is there a compelling argument for that? It feels like it must be intentional. If not, I would suggest adding that because I'm pretty sure it would have spared me a couple of hours just by realising quickly that it takes `std::array` from the wrong header. Thank you in advance and keep up the great work! Julian