3418 – link error with cast(ulong)(ulong*real)

test case:
ulong a = 1; 
a = cast(ulong)(a * 2.0L);
ERROR message: 
OPTLINK (R) for Win32 Release 8.00.1
Copyright (C) Digital Mars 1989-2004 All rights reserved.
C:\d\dmd2\windows\bin\..\lib\SNN.lib(u64_ldbl) Offset FFE74H Record Type 0091
 Error 1: Previous Definition Different : ___LDBLULLNG

Created attachment 588 [details] 
test case with template use and comments

I get the same error, but in a slightly different context. I tried the case from ZY Zhou on DMD 2.041, and it still fails.
The different case that I'm seeing is this.
This links fine.
	real y = 99.5L;
	ulong x = cast(ulong) y;
But if I put it after the following call, I get the link error.
	BinOp!(ulong, real).P( 99L );
	// where P is defined like this
	template BinOp(T, U)
	{
		void Q( U u )	{}
		void P( T t )	{ Q( cast(U) t ); }
	}
Then compiling with -O gets rid of the error. I do have a case where the error doesn't go away with the -O flag. The following is all in main.
	BinOp!(ulong, real).P( 99L );
	real y = 99.5L;
	void Q( ulong l )
	{
	}
	void P( real r )
	{
		Q( cast(ulong) r );
	}
	// B: -O doesn't fix this
	P( y );
Of course, getting rid of the BinOp.P call gets rid of the error as before.
Sorry if this is confusing. I've attached a file that might show this a little more clearly. Picking line A or one line B by itself will not bring out the error. It involves enabling A and one of the line Bs.

http://www.dsource.org/projects/druntime/changeset/379