On 04/11/2018 10:02 AM, Jakub Jelinek wrote:
> On Wed, Apr 11, 2018 at 09:48:05AM +0200, Andreas Krebbel wrote:
>> c-c++-common/attr-nonstring-3.c fails on IBM Z. The reason appears to be
>> that we provide builtin implementations for strcpy and stpcpy. The
>> warnings currently will only be emitted when expanding these as normal
>> calls.
>>
>> Bootstrapped and regression tested on x86_64 and s390x.
>>
>> Ok?
>>
>> gcc/ChangeLog:
>>
>> 2018-04-11 Andreas Krebbel <kreb...@linux.vnet.ibm.com>
>>
>> * builtins.c (expand_builtin_strcpy): Invoke
>> maybe_warn_nonstring_arg.
>> (expand_builtin_stpcpy): Likewise.
>
> Don't you then warn twice if builtin implementations for strcpy and stpcpy
> aren't available or can't be used, once here and once in calls.c?
Looks like this could happen if the expander is present but rejects expansion.
I basically copied
this from the strcmp builtin which looks like possibly running into the same
problem:
/* Check to see if the argument was declared attribute nonstring
and if so, issue a warning since at this point it's not known
to be nul-terminated. */
tree fndecl = get_callee_fndecl (exp);
maybe_warn_nonstring_arg (fndecl, exp);
if (result)
{
/* Return the value in the proper mode for this function. */
machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
if (GET_MODE (result) == mode)
return result;
if (target == 0)
return convert_to_mode (mode, result, 0);
convert_move (target, result, 0);
return target;
}
/* Expand the library call ourselves using a stabilized argument
list to avoid re-evaluating the function's arguments twice. */
tree fn = build_call_nofold_loc (EXPR_LOCATION (exp), fndecl, 2, arg1, arg2);
gcc_assert (TREE_CODE (fn) == CALL_EXPR);
CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
return expand_call (fn, target, target == const0_rtx);
-Andreas-
