https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100289
--- Comment #28 from Richard Purdie <richard.purdie at linuxfoundation dot org> --- For what it is worth, I just ran into this with gcc 16.2 trying to build an avr cross compiler to run on an arm system on an x86_64 build host. I attached a config.log for libgcc as had been requested. This one is one that passed as I used --disable-gconv but you can see it finds mman.h which it shouldn't have been able to from those sysroots specified.
