Internal Error

[Russell Lewis]

Neil Vice wrote:
> I've encountered the following error in DMD 2.012:
> 
>     Internal error: ..\ztc\cod1.c 1662
> 
> I would submit a bug report except that I can't seem to determine a simple 
> case that produces the bug, so I guess I'm looking for some assistance in 
> narrowing down the problem.
> 
> I have two structs, one representing a time-stamp and another representing a 
> time-period. They both implement opSub. Nested within a method in a class 
> within a class in a seperate package I have some code along the lines of:
> 
>     auto result = a - (b - c);
> 
> where a is a TimePeriod and b & c are TimeStamps.
> 
> If I replace this line with:
> 
>     auto _result = b - c;
>     auto result = a - _result;
> 
> the Internal error goes away.
> 
> I have attempted to construct a simple case with two similar structs with 
> opSub methods and a main() containing the problem expression, however I 
> cannot reproduce the error.
> 
> Any suggestions on where to go from here? 

Generally, I do binary search on my code.  I comment out huge swaths of 
code that I think might be irrelevant, then recompile.  If the failure 
goes away, then I only comment out half of that section, and try again.

It's a painful, iterative process, but it usually works.  Most times I 
can reduce 1000s of lines of code down to a 10-line example.

If you don't have time for that, I would recommend that you still post 
the bug with your complete code.  Maybe somebody else will have time. 
IMHO, it ought to be recorded.