Why C++ compiles slowly

[Walter Bright]

Steven Schveighoffer wrote:
> On Mon, 23 Aug 2010 13:41:07 -0400, Walter Bright 
> <newshound2 at digitalmars.com> wrote:
> 
>> Steven Schveighoffer wrote:
>>> I get a long list of functions proceeding at a reasonable rate.  I've 
>>> done that in the past, I feel it's some sort of inner loop problem.  
>>> Essentially, something takes way longer to compile than it should, 
>>> but way longer on the order of .05 seconds instead of .005 seconds, 
>>> so you don't notice it normally.  But somehow my library is able to 
>>> harness that deficiency and multiply by 1000.
>>>  I don't know, it doesn't seem like dcollections should evoke such a 
>>> long compile time.
>>
>> with or without -O ?
> 
> The compile line is:
> 
> dmd -unittest unit_test.d dcollections/*.d dcollections/model/*.d
> 
> Where unit_test.d is a dummy main.

You could try running dmd under a profiler, then.