On Mon, Sep 28, 2015 at 2:05 PM, Bernd Schmidt <bschm...@redhat.com> wrote:
> On 09/28/2015 02:00 PM, Jakub Jelinek wrote:
>>
>> On Mon, Sep 28, 2015 at 01:27:32PM +0200, Bernd Schmidt wrote:
>>>>
>>>> I've removed obstack_ptr_grow for arrays with known sizes after this
>>>> review:
>>>> https://gcc.gnu.org/ml/gcc-patches/2014-10/msg02210.html
>>>
>>>
>>> That's unfortunate, I think that made the code less future-proof. IMO we
>>> should revert to the obstack method especially if Thomas -v patch goes
>>> in.
>>
>>
>> Why? If the number of arguments is bound by a small constant, using
>> automatic fixed size array is certainly more efficient, and I really don't
>> see it as less readable or maintainable.
>
>
> The code becomes harder to modify, with more room for error, and you no
> longer have consistency in how you build argv arrays within the same file.
> The obstack method is pretty much foolproof and doesn't even remotely allow
> for the possibility of a buffer overflow, and adding new arguments, even
> conditionally, is entirely trivial. Efficiency is really not an issue for
> building arguments compared to the cost of executing another binary.
I agree that obstacks are better here. Efficiency shouldn't matter here.
But we're in C++ now so can't we statically construct the array with
sth like
const char *new_argv[] = { "objcopy", ... };
? Thus have the compiler figure out the number of args. That would work
for me as well.
Richard.
>
> Bernd
