I recompiled phobos (dmd-0.102/gcc-3.3.2/linux) and unittest.d with the
"-unittest" flag enabled for all(including internal/gc/*.d) d-source files.

Run ./unittest and got an interesting error (only offending lines shown here):
> [_d_arraycopy] f = 0xbffff81c,2, t = 0x401a7ad4,4, size = 1
> <<== caught here <<==
> [_d_arraycopy] f = 0x8074384,20, t = 0x401a6a20,20, size = 1
> Error: lengths don't match for array copy

The actual data (ca. 500KB):
http://dmd.kuehne.cn/phobos__bug_d_arraycopy.zip
content:
    _d_arraycopy_bug.output.txt
    libphobos.a
    phobos___d_arraycopy_bug.diff
    unittest
    unitted.d
    unittest.o

Thomas