Created attachment 427834 [details] cross-x86_64-isis-linux-gnu-gcc-stage1.log.xz sys-devel/gcc:5 have new use flag "jit", which installs not slotted library "/usr/lib/libgccjit.so.0.0.1". Emerging cross-gcc, with "jit" enabled lead to path conflict. Probably this bug, also, belong to GCC, but for now crossdev can (should?) explicitly disable "jit" use flag.
Created attachment 427836 [details, diff] crossdev.patch Proposed patch to enable crossdev use with sys-devel/gcc:5[jit]
*** This bug has been marked as a duplicate of bug 569608 ***