DMD 0.164: Possible bug in order of evaluation

[Klaus Oberhofer]

Walter Bright <newshound at digitalmars.com> wrote in news:eca93v$ddt$1
@digitaldaemon.com:

> Klaus Oberhofer wrote:
>> While porting some C-Code to D I had a possible bug that has to do with 
>> the order of evaluation of the post increment operator. 
>> The following C sample
> [...]
>>     testarray_b[i++] = 1U << (16 - i);
> [...]
>> Could someone confirm this as a bug ?
> 
> In the source code, yes. Depending on order of evaluation of side 
> effects is an error in D as well as an error in C and C++.
> 

Thank you for the lesson, Walter :)

Under normal circumstances I stay away from such constructs like the devil
from holy water. But I converted parts of unarj.c to D, and this 
wonderful piece of code is a good example for your recently proposed 
new D coding style :)
My failure was, that I tried to stay away from the internals of unarj.
Never mind, I'm here to learn and this way I learn much about D and
as a side effect about the internals of dictionary coders.
Greets

Klaus


BTW, one of my C books states that ANSI C compliant compilers are not 
allowed to move/discard code unless they can prove there are no 
side effects. It further says that on non compliant compilers the behaviour
is undefined.