Hey all- I got this issue in my GH account I use for building Swift for Fedora: https://github.com/tachoknight/swift-lang-packaging-fedora/issues/2. The TL;DR is that the person was trying to build Swift on Rawhide which he moved to from an older version of Fedora. This tracks with something I discovered as well: I have a current Fedora VM (not Rawhide) that I’ve been upgrading from version to version for several years now, and suddenly it cannot build Swift due to a series of bizarre error messages like: … /usr/lib/gcc/x86_64-redhat-linux/12/../../../../include/c++/12/set:60:10: note: in file included from /usr/lib/gcc/x86_64-redhat-linux/12/../../../../include/c++/12/set:60: #include <bits/stl_tree.h> ^ /usr/lib/gcc/x86_64-redhat-linux/12/../../../../include/c++/12/bits/stl_tree.h:2008:5: error: missing '#include "gcc/x86_64-redhat-linux/12/../../../../include/c++/12/bits/stl_pair.h"'; 'pair' must be declared before it is used pair<typename _Rb_tree<_Key, _Val, _KeyOfValue, ^ /usr/lib/gcc/x86_64-redhat-linux/12/../../../../include/c++/12/bits/stl_pair.h:185:12: note: declaration here is not visible struct pair … However, using mock or a container, it builds fine, Rawhide, F37, whatever. I’m guessing there’s a setting or environment variable or … ? that is present on my and his systems that doesn’t exist in a new container and thus I nor he can build it, while a container and mock can (and I’ve confirmed with scratch koji builds multiple times). Might anyone have an idea where to check to see what might be causing this? I can’t pin down exactly when this started to happen except that it has been _relatively_ recently, perhaps just in the past few months. Thanks for any suggestions! Ron