example build failure: https://sourceware.org/ml/gdb/2016-11/msg00017.html /home/joel/rtems-4.11-work/rtems-source-builder/rtems/sources/b-mips/sim/mips/../../../gdb-7.12/sim/mips/mips.igen:1254: undefined reference to `check_u64' this is due to the r3900 cpus lacking markings for the check_u64 in the igen code. should be fixed by: https://sourceware.org/ml/gdb-patches/2016-11/msg00287.html
fix pushed to master & 7.12 branch