Segfault while compiling simple program

[Saurabh Das via Digitalmars-d-learn]

struct xlref
{
     ushort rwFirst;
     ushort rwLast;
     ubyte colFirst;
     ubyte colLast;
}

struct xlmref
{
     ushort count;
     xlref reflist;
}

Mac OS X (dmd 2.069.0)
===================
dmd  dprob.d
Segmentation fault: 11

Windows (dmd 2.069.2)
==================
dmd -v -m64 dprob.d
binary C:\D\dmd2\windows\bin\dmd.exe
version v2.069.2
config C:\D\dmd2\windows\bin\sc.ini
parse xlcall_wrap2
importall xlcall_wrap2
import object 
(C:\D\dmd2\windows\bin....\src\druntime\import\object.d)
semantic xlcall_wrap2

object.Error@(0): assert(0) or HLT instruction

0x0040496F
0x00404CF8
0x004CF2B6
0x004565A7
0x0044EAB0
0x004BF99E
0x74F757F9 in MultiByteToWideChar
0x76F2139E in RtlQueryProcessDebugInformation
0x76F21340 in RtlQueryProcessDebugInformation
0x76F21190 in RtlQueryProcessDebugInformation

What gives?

Saurabh