https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87438
--- Comment #2 from Zach van Rijn <me at zv dot io> ---
Using GCC 8-20180706 snapshot,
gcc -c -O2 -fPIC grapes.c
during RTL pass: reload
grapes.c: In function 'smaxval_r8':
grapes.c:57:1: internal compiler error: in gen_reg_rtx, at emit-rtl.c:1155
}
^
0x408422 gen_reg_rtx(machine_mode)
../../src_gcc/gcc/emit-rtl.c:1155
0x5e6ba6 force_reg(machine_mode, rtx_def*)
../../src_gcc/gcc/explow.c:665
0xc25604 gen_movdf(rtx_def*, rtx_def*)
../../src_gcc/gcc/config/microblaze/microblaze.md:1224
0x5fe6c5 insn_gen_fn::operator()(rtx_def*, rtx_def*) const
../../src_gcc/gcc/recog.h:301
0x5fe6c5 emit_move_insn_1(rtx_def*, rtx_def*)
../../src_gcc/gcc/expr.c:3666
0x603b45 gen_move_insn(rtx_def*, rtx_def*)
../../src_gcc/gcc/expr.c:3782
0x80e858 gen_reload
../../src_gcc/gcc/reload1.c:8740
0x8171a7 emit_input_reload_insns
../../src_gcc/gcc/reload1.c:7632
0x8171a7 do_input_reload
../../src_gcc/gcc/reload1.c:7919
0x8171a7 emit_reload_insns
../../src_gcc/gcc/reload1.c:8107
0x8171a7 reload_as_needed
../../src_gcc/gcc/reload1.c:4647
0x81ab76 reload(rtx_insn*, int)
../../src_gcc/gcc/reload1.c:1050
0x7044ea do_reload
../../src_gcc/gcc/ira.c:5477
0x7044ea execute
../../src_gcc/gcc/ira.c:5649
