Re: [Xenomai-core] [PATCH][SOLO] add more warnings

[Philippe Gerum <rpm@xenomai.org>]

Robert Schwebel wrote:
> Contrary to what one would assume, -Wall doesn't warn on everything. It
> turned out to add a few more options, like -Wsign-compare, -Wfloat-equal
> and -Wformat-security, which is what the patch below does.
> 
> When running with these options, we get the following warnings:
> 
> kernelLib.c: In function 'kernelInit':
> kernelLib.c:63: warning: comparison between signed and unsigned
> msgQLib.c: In function 'msgQReceive':
> msgQLib.c:165: warning: comparison between signed and unsigned
> msgQLib.c: In function 'msgQSend':
> msgQLib.c:227: warning: comparison between signed and unsigned
> msgQLib.c:237: warning: comparison between signed and unsigned
> taskLib.c: In function 'taskSpawn':
> taskLib.c:382: warning: signed and unsigned type in conditional expression
> pt.c: In function 'get_pt_from_id':
> pt.c:56: warning: comparison between signed and unsigned
> pt.c:58: warning: comparison between signed and unsigned
> queue.c: In function 'get_queue_from_id':
> queue.c:49: warning: comparison between signed and unsigned
> queue.c: In function '__q_send':
> queue.c:224: warning: comparison between signed and unsigned
> queue.c: In function '__q_broadcast':
> queue.c:311: warning: comparison between signed and unsigned
> queue.c: In function '__q_receive':
> queue.c:365: warning: comparison between signed and unsigned
> rn.c: In function 'get_rn_from_id':
> rn.c:41: warning: comparison between signed and unsigned
> sem.c: In function 'get_sem_from_id':
> sem.c:41: warning: comparison between signed and unsigned
> task.c: In function 'find_psos_task':
> task.c:54: warning: comparison between signed and unsigned
> task.c: In function 'find_psos_task_or_self':
> task.c:86: warning: comparison between signed and unsigned
> task.c: In function 'get_psos_task':
> task.c:110: warning: comparison between signed and unsigned
> task.c: In function 'get_psos_task_or_self':
> task.c:131: warning: comparison between signed and unsigned
> task.c:140: warning: comparison between signed and unsigned
> task.c: In function 'check_task_priority':
> task.c:232: warning: comparison between signed and unsigned
> tm.c: In function 'get_tm_from_id':
> tm.c:43: warning: comparison between signed and unsigned
> 
> I've looked into the first ones only yet and it looks to me like the
> type definitions have to be reviewed carefully. For example, TASK_ID is
> defined to be unsigned long, whereas the vxworks documentation [1] looks
> more like if we need 'int' there. Which also makes me wonder if vxworks
> has a special idea about what 'int' is;

VxWorks assumes 32bit and sizeof(void *) == sizeof(int), unfortunately. See
taskSpawn() for instance.

 guessing from [2] it looks like
> it assumes sint32_t, so in order to fix this on 64 bit boxes, shouldn't
> these cases be converted to use the inttypes.h definitions?
>

Did you mean stdint.h? What we need is an integer type which is able to carry a
pointer on 32/64bit platforms, so we should rather use intptr_t I guess, as per
C99, which expands as a long type. Object ids as unsigned long is a left over
from the co-kernel version, where we use actual integer handles returned from
kernel space, and not pointers in disguise. Will fix, thanks.

> However, somebody with more vxworks knowledge than myself should have a
> look at this.
> 
> Signed-off-by: Robert Schwebel <r.schwebel@domain.hid>
> 
> [1] http://spacegrant.colorado.edu/~dixonc/vxworks/docs/vxworks/ref/taskLib.html#taskActivate
> [2] http://www.xs4all.nl/~borkhuis/vxworks/vxw_pt6.html
> 
> ---
>  configure.in |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 

Merged, thanks.

> Index: xenomai-solo/configure.in
> ===================================================================
> --- xenomai-solo.orig/configure.in	2008-03-28 19:17:23.000000000 +0100
> +++ xenomai-solo/configure.in	2008-03-28 19:19:15.000000000 +0100
> @@ -163,7 +163,8 @@
>  dnl Exported CFLAGS and LDFLAGS
>  XENO_USER_APP_CFLAGS=$XENO_USER_CFLAGS
>  XENO_USER_APP_LDFLAGS=$XENO_USER_LDFLAGS
> -XENO_USER_CFLAGS="$XENO_USER_CFLAGS -Wall -pipe -fstrict-aliasing $gcc_w_noalias"
> +XENO_USER_CFLAGS="$XENO_USER_CFLAGS -Wall -Wsign-compare -Wfloat-equal -Wformat-security"
> +XENO_USER_CFLAGS="$XENO_USER_CFLAGS -pipe -fstrict-aliasing $gcc_w_noalias"
>  
>  if test x$debug_symbols = xy; then
>     XENO_USER_CFLAGS="-g -O0 $XENO_USER_CFLAGS -D__SOLO_DEBUG__"
> 


-- 
Philippe.