Compiler warning: type punned pointers - patch required?

["Uwe Kindler" <uwe_kindler at web dot de>]

Hello,

I currently finish the Renesas EDOSK-2674 port an try to remove all warnings
from build process.
I use the a h8300-elf toolchain based on gcc-3.3 branch snapshot dated 15th
December 2003. During RedBoot build I get a lot of these warnings:

/ecos-d/ecos/packages/redboot/current/src/fconfig.c:469:
warning:dereferencing type-punned pointer will break strict-aliasing rules
/ecos-d/ecos/packages/redboot/current/src/fconfig.c:471:
warning:dereferencing type-punned pointer will break strict-aliasing rules
/ecos-d/ecos/packages/redboot/current/src/fconfig.c:473:
warning:dereferencing type-punned pointer will break strict-aliasing rules
/ecos-d/ecos/packages/redboot/current/src/fconfig.c:475:
warning:dereferencing type-punned pointer will break strict-aliasing rules
/ecos-d/ecos/packages/redboot/current/src/fconfig.c:477:
warning:dereferencing type-punned pointer will break strict-aliasing rules

Other files like load.c, mfill.c also cause such warnings. If I inspect
thefconfig.c source wich caused these warnings, then I can see that
functions are called this way:

init_opts(&opts[0], 'l', false, OPTION_ARG_TYPE_FLG,
              (void **)&list_only, (bool *)0, "list configuration only");

but they are defined this way:

void
init_opts(struct option_info *opts, char flag, bool takes_arg,
          int arg_type, void *arg, bool *arg_set, char *name);

Therefore the cast of (void **)&list_only for the void *arg function
argument causes the warning. If I change the function call this way:

init_opts(&opts[0], 'l', false, OPTION_ARG_TYPE_FLG,
              (void *)&list_only, (bool *)0, "list configuration only");

the warnings go away.

So my question is: Is there a special reason for casting to void ** when
void * is required. If you would say this is a bug then I would supply a
patch which removes all theses warnings.

Regards, Uwe