Re: warnings in ProjectCenter and GNUstep detect

[David Chisnall]

On 7 Apr 2011, at 15:42, Riccardo Mottola wrote:

> Hi,
>> PCMiscPrefs.m:194:15: warning: equality comparison with extraneous 
>> parentheses
>> [-Wparentheses]
>>   if ((sender == debuggerField))
>>        ~~~~~~~^~~~~~~~~~~~~~~~
>> PCMiscPrefs.m:194:15: note: use '=' to turn this equality comparison into an
>> assignment
> 
> Could it be that GCC has the suggestion of the double parentheses instead ? I 
> remember something about the double () being suggested by gcc but I don't 
> remember when. I put it in when it complains.

Nope, GCC recommends parentheses for this:

if (sender = debuggerField)

It will say that you probably mean ==, and if you don't then you should use an 
extra set of parentheses.  Clang is warning you here because the GCC warning 
means that double parentheses are used to protect a=b type conditionals, and 
this isn't one but could be a typo if you meant one.

Changing this to:

if (sender == debuggerField)

Or:

if ((sender = debuggerField))

Will make both compilers happy.  The first form is almost certainly what was 
meant, in this case, although I can't be completely sure without seeing the 
surrounding code.

David

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