On 2013-03-07 20:28, Dimitry Andric wrote:
> On 2013-03-07 18:24, Tijl Coosemans wrote:
>> Whatever the command line arguments, running c89 almost always results in
>> the following output. Anyone else seeing this?
>>
>> c89: illegal option -- 1
>> usage: c89 [-cEgOs] [-D name[=value]] ... [-I directory] ... [-L directory] 
>> ...
>>             [-o outfile] [-U name] ... operand ...
>>
>>         where operand is one or more of file.c, file.o, file.a
>>         or -llibrary
> 
> Does anybody ever actually use this tool, really? :-)
> 
> In any case, what happens is that /usr/bin/c89 builds up an argv[]
> array, prepending the flags "-std=iso9899:199409" and "-pedantic" to the
> other arguments, but it sets argv[0] to "/usr/bin/c89" too.
> 
> If /usr/bin/cc is gcc, this causes no problems, since gcc always runs
> /usr/libexec/cc1 for its first stage compilation process.  It basically
> ignores the value of argv[0].
> 
> When /usr/bin/cc is clang, however, it uses argv[0] to run its first
> stage compilation, with -cc1 as the first argument.  So this will run
> /usr/bin/c89 yet again, and that complains about the unrecognized '1'
> option.
> 
> It can be solved very easily, by letting c89.c set argv[0] to
> /usr/bin/cc instead, similar to c99.c, as with this diff:
> 
> Index: usr.bin/c89/c89.c
> ===================================================================
> --- usr.bin/c89/c89.c    (revision 247448)
> +++ usr.bin/c89/c89.c    (working copy)
> @@ -72,7 +72,7 @@ main(int argc, char **argv)
>      Argv.a = malloc((argc + 1 + N_ARGS_PREPENDED) * sizeof *Argv.a);
>      if (Argv.a == NULL)
>          err(1, "malloc");
> -    Argv.a[Argc++] = argv[0];
> +    Argv.a[Argc++] = CC;
>      for (j = 0; j < N_ARGS_PREPENDED; ++j)
>          Argv.a[Argc++] = args_prepended[j];
>      while ((i = getopt(argc, argv, "cD:EgI:l:L:o:OsU:")) != -1) {
> 
> 
>> Also, I seem to remember a discussion about making -std=gnu89 the default
>> for clang when run as "cc", but nothing seems to have changed. Could this
>> be picked up again, because there are in fact subtle semantic differences
>> between gnu89 inline and c99 inline that old code may rely on.
> 
> Why on earth would you want gnu89 still as the default in 2013?  I would
> rather have it default to C11, but the support for this isn't complete
> yet... :-)

Because it's the practical thing to do? Old code/makefiles can't possibly
be expected to know about compilers of the future, while new code can be
expected to add -std=c11.

Attachment: signature.asc
Description: OpenPGP digital signature

Reply via email to