With:
cc -g -m68040 -Os -Os -Werror -Wall -Wstrict-prototypes -Wmissing-prototypes  -Wpointer-arith -Wno-uninitialized -Wno-main -msoft-float -I. -I../../../../arch -I../../../.. -nostdinc -DHZ="0x3c" -DM68040 -DLKM -DDIAGNOSTIC -DGRF_COMPAT -DMAXUSERS=32 -D_KERNEL -Dmac68k  -c ../../../../arch/m68k/m68k/db_trace.c
cc1: warnings being treated as errors
../../../../arch/m68k/m68k/db_trace.c: In function `db_stack_trace_print':
../../../../arch/m68k/m68k/db_trace.c:506: warning: implicit declaration of function `_C_LABEL_STRING'
../../../../arch/m68k/m68k/db_trace.c:506: warning: passing arg 1 of `strcmp' makes pointer from integer without a cast

Oops.

A quick grep seems to show that _C_LABEL_STRING is defined as part of the
ELF bits (cdefs_elf.h).  WHich seems out of place because none of the m68k 
ports are ELF yet, right?

So I took the quick and dirty way out and just used:

#define _C_LABEL_STRING(x) x since _C_LABEL_STRING seems misplaced here
anyways, ELF or not.

Hmm.

- alex