Hi!
On Sun, 27 Nov 2016 17:14:26 +0100, Samuel Thibault <samuel.thiba...@gnu.org>
wrote:
> Thomas Schwinge, on Sat 26 Nov 2016 19:53:34 +0100, wrote:
> > When changing the GDB source code to use kern_return_t (or int) instead
> > of error_t, I still see hurd.h:__hurd_fail and
> > hurd/signal.h:HURD_MSGPORT_RPC choke on their own error_t usage:
> >
> > $ echo -e '#include <errno.h>\n#include <mach.h>\n#include
> > <hurd.h>\n#include <hurd/signal.h>\nvoid f(){ kern_return_t err = 0; err =
> > thread_get_state(0,0,0,0); err = HURD_MSGPORT_RPC(0,0,0,0); }' | g++
> > -D_GNU_SOURCE -x c++ - -S -o /dev/null -O2
>
> Don't use 0, but ESUCCESS.
;-) I do know about ESUCCESS (I added it), but the literal 0 (int) here
are to model the fact that Mach API calls have a return type of
kern_return_t (int). (Thus, I will change GDB's "err" variables from
error_t to kern_return_t.)
> > In file included from /usr/include/errno.h:35:0,
> > from <stdin>:1:
> > /usr/include/hurd.h: In function ‘int __hurd_fail(error_t)’:
> > /usr/include/hurd.h:60:13: error: invalid conversion from ‘int’ to
> > ‘error_t {aka __error_t_codes}’ [-fpermissive]
> > err = EIEIO;
> > ^
> > /usr/include/hurd.h:64:13: error: invalid conversion from ‘int’ to
> > ‘error_t {aka __error_t_codes}’ [-fpermissive]
> > err = ENOMEM;
> > ^
> > /usr/include/hurd.h:68:13: error: invalid conversion from ‘int’ to
> > ‘error_t {aka __error_t_codes}’ [-fpermissive]
> > err = EINVAL;
This remains to be fixed; can you please commit your patch?
> The HURD_MSGPORT_RPC seems missing casts between kern_error and error_t
> indeed.
Thanks for changing this code. Though, the explicit casts are also not
completely ideal, as they now hide other kinds of problems, for example:
$ echo -e '#include <errno.h>\n#include <hurd.h>\n#include
<hurd/signal.h>\nvoid f(){ error_t err = HURD_MSGPORT_RPC(&err,&err,&err,&err);
}' | gcc -D_GNU_SOURCE -x c - -S -o /dev/null -O2
... in C compilation mode now no longer diagnoses "error: incompatible
types when assigning [...]". Oh well... ;-/
Grüße
Thomas
