I'm working on a complex project for my company.
It's a text-parser that handles complex/ambiguos word-based grammars. It reads a set of xml files that define rules, build some structures (trees, dictionaries, etc..) and then parses your phrases.  It works fine.

I compile sources in this (simple) way:
dmd -c *.d   (three source files)

If i link objects with dmd execution of unit tests takes:

Parsing: 722 ms, 419 μs, and 3 hnsecs

real 5m10.199s
user 5m9.771s
sys 0m0.236s


using gcc as linker:

Parsing: 425 ms, 677 μs, and 8 hnsecs

real 0m13.919s
user 0m13.845s
sys 0m0.088s


unittest outputs are identical and execution time of test phrases has similar speed but dmd version takes a lot of time parsing xml and building trees and other structures.

I can't post company code, but i wonder if this is a known issue... If not i'll try to write some code to reproduce this problem...

Configuration:
Ubuntu 11.10 64bit
DMD64 D Compiler v2.056
gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3)