The dmd source assumes x86 longdoubles which are not available on ARM (and possible other systems).
This leads to an assertion error in PortInitializer. The workaround is to check for the size of
longdouble.
The D Programming Language
Compiler Front End Source
Copyright (c) 1999-2013, by Digital Mars
http://www.digitalmars.com/
All Rights Reserved
This is the source code to the front end Digital Mars D compiler.
It covers the lexical analysis, parsing, and semantic analysis
of the D Programming Language defined in the documents at
http://dlang.org/
These sources are free, they are redistributable and modifiable
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version (attached as gpl.txt),
or the Artistic License (attached as artistic.txt).
The optimizer and code generator sources are
covered under a separate license, backendlicense.txt.
It does not apply to anything else distributed by Digital Mars,
including D compiler executables.
-Walter Bright