Re: [PATCH 0/5] Remove a few hurdles of compiling with clang

Simon Marchi
2017-06-13T11:08:53Z

On 2017-06-13 13:06, Pedro Alves wrote:
> On 06/13/2017 11:23 AM, Simon Marchi wrote:
>
>> I have a concrete example that is currently in the pipeline. I hit
>> this warning/error:
>>
>> /home/emaisin/src/binutils-gdb/gdb/nat/x86-dregs.c:209:7: error:
>> variable 'i' is incremented both in the loop header and in the loop
>> body [-Werror,-Wfor-loop-analysis]
>> i++;
>> ^
>> /home/emaisin/src/binutils-gdb/gdb/nat/x86-dregs.c:199:32: note:
>> incremented here
>> ALL_DEBUG_ADDRESS_REGISTERS (i)
>> ^
>>
>> which would require changing this code:
>>
>> ALL_DEBUG_ADDRESS_REGISTERS (i)
>> {
>> ...
>> i++;
>> }
>>
>> to either the expansion of the macro:
>>
>> for (int i = DR_FIRSTADDR; i <= DR_LASTADDR; i += 2)
>> {
>> ...
>> }
>
> This, IMO. I think it's just that one place?

It's the only instance of that particular problem, yes.

>> or to a new macro that would take into account the increment:
>>
>> ITER_DEBUG_ADDRESS_REGISTERS (i, i += 2) // other users would use
>> i++
>> {
>> ...
>> }
>>
>
> That'd obfuscate too much for no real benefit, IMO.

Agreed.

Simon