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

[Simon Marchi <simon.marchi@polymtl.ca>]

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