https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88266
Bug ID: 88266
Summary: nonsense warning about parentheses for comparison
Product: gcc
Version: 7.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jason.kraftch...@cd-adapco.com
Target Milestone: ---
For this code compiled with -Wall:
bool xnor( bool a, bool b, bool c, bool d )
{ return a != b != c != d; }
I get these warnings:
/tmp/xnor.cc: In function ‘bool xnor(bool, bool, bool, bool)’:
/tmp/xnor.cc:2:14: warning: suggest parentheses around comparison in operand
of ‘!=’ [-Wparentheses]
{ return a != b != c != d; }
~~^~~~
/tmp/xnor.cc:2:19: warning: suggest parentheses around comparison in operand
of ‘!=’ [-Wparentheses]
{ return a != b != c != d; }
~~~~~~~^~~~
The order of evaluation of these comparisons doesn't matter, so parentheses add
nothing. One could even argue that adding them would be detrimental because it
gives the false impression that the order matters.
