The relevant errors in the log are:
Undefined symbols for architecture x86_64:
"_cfun", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_epilogue_completed", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_cf_protection", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_finite_math_only", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_fp_int_builtin_inexact", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_peephole2", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_pic", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_rounding_math", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_trapping_math", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_flag_unsafe_math_optimizations", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_insn", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_arch_features", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_cmodel", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_fpmath", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_isa_flags", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_isa_flags2", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_pmode", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_tls_dialect", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_ix86_tune_features", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_operands", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_optimize", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_reload_completed", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_reload_in_progress", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_rtx_class", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_target_flags", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_this_target_flag_state", referenced from:
___cxx_global_var_init.99 in gencondmd.o
"_x86_prefetch_sse", referenced from:
___cxx_global_var_init.99 in gencondmd.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[3]: *** [build/gencondmd] Error 1
