From: "K.A.R.L." <farega AT usc DOT es>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Linking Multi-File Project w/Templates
Date: Fri, 31 Jan 1997 15:43:01 +0100
Organization: Universidade de Santiago
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Message-ID: <32F204F5.4A21@usc.es>
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To: djgpp AT delorie DOT com
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Mike Habicher wrote:
> 
> I still can't get ld to link my multi-file
> project.  The project involves a class that
> has its declarations stored in a .h file,
> which is included in two C++ files: the first
> one containing the actual code of the class'
> member functions, and the second one which is
> supposed to exercise the class to locate any
> possible coding errors.
> 
> The class uses templates, and while the source
> files compile without errors, I get a whole
> bunch of "unresolved" errors when I try to link
> them together.
> 
> Is there some sort of parameter I need to
> specify during the compile to get templates
> to compile properly?  Or some modification I
> need to make to source files?

	When I started working with DJGPP I had a similar problem with
templates, and found the solution on the gcc info file, in the section
devoted to C++ extentions.

	The idea is to compile the modules with the -fno-implicit-templates
switch, and add in the file where you define the classes an explicit
declaration of the concrete instances you need.

	For example, you have the template class foo:

template<class T> foo<T>
	{
	// all the stuff
	}

// explicit instantiations for each type you need
template class foo<int>
template class foo<double>

	This way it worked for me. Hope this helps!