CMake enforces -fno-fat-lto-objects unconditionally for GCC + IPO
Building qtbase 6 with -DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON returns errors when stripping the static libraries. The issue is caused by GNU.cmake which appends -fno-fat-lto-objects to __lto_flags [1]
It makes sense for shared libraries, but not for static ones.
[1] https://gitlab.kitware.com/cmake/cmake/-/blob/master/Modules/Compiler/GNU.cmake#L80
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