qtcreator can no longer load clazy or clang-tidy plugins

After updating to clang 8.0, we got a bug report downstream about qtcreator no longer being able to load the clazy plugin (it also affects clang-tidy), and instead showing an "unable to find plugin" error [1]. After some research this turns out to be caused by 5f2efcd632af7e02e05ec9473f3875caf449ecd5. Strangely, loading the plugin from the clang command itself still works (/usr/bin/clang -fsyntax-only -Xclang -load -Xclang ClazyPlugin.so -Xclang -add-plugin -Xclang clazy foo.cpp).

Note that the qtcreator binaries distributed by Qt use a patched version of clang which statically links the plugins [2], so they're likely not affected. In order to make qtcreator work with unpatched clang, we have to apply a patch to load the plugins at runtime in qtcreator [3]. This used to work fine until 5f2efcd632af7e02e05ec9473f3875caf449ecd5. Is this a bug or expected behavior? And in the latter case, any ideas about how to make it work again?


[1] https://bugs.archlinux.org/task/62221
[2] https://code.qt.io/cgit/clang/clang.git/commit/?h=release_80-based&id=f16c0ba7e94c6b34d516bb79ac22482fb4d96765
[3] https://git.archlinux.org/svntogit/packages.git/tree/trunk/qtcreator-clang-plugins.patch?h=packages/qtcreator