6.2.0 based devel/powerpc64-gcc rejects sys/powerpc/powerpc/db_trace.c for very old code

[John Baldwin]

On Tuesday, December 27, 2016 12:37:08 AM Mark Millard wrote:
> I have submitted:
> 
> Bug 215600 - devel/powerpc64-gcc based buildkernel: sys/powerpc/powerpc/db_trace.c rejected for: '__builtin_frame_address' with a nonzero argument is unsafe
> 
> sys/powerpc/powerpc/db_trace.c -r132070 2004-Jul-12 is when this
> __builtin_frame_address use was introduced:
> 
> void
> db_trace_self(void)
> {
>         db_addr_t addr;
> 
>         addr = (db_addr_t)__builtin_frame_address(1);
>         db_backtrace(curthread, addr, -1);
> }
> 
> 
> 
> head was at -r310556 for this discovery but with a patch for libdwarf
> in ctfconvert to enable buildkernel to get this far. I have not yet
> updated to the 6.3.0 based devel/powerpc64-gcc .

Try using '0' instead of '1'.  You might get an extra frame in the backtrace
compared to before.  A simple way to test is to add 'options KDB_TRACE' and
then trigger a panic (e.g. sysctl debug.kdb.panic=1)

-- 
John Baldwin