Re: [boost] PCH compiler limit error

From: Sebastian Redl (sebastian.redl_at_[hidden])
Date: 2008-03-27 18:13:55

Robert Dailey wrote:
> 2>c:\it\tfs\crusades\sdks\boost\boost\filesystem\operations.hpp(827) : error
> C3859: virtual memory range for PCH exceeded; please recompile with a
> command line option of '-Zm112' or greater
>
> The recommended fix in the error text resolves the problem, but I'm
> wondering why this is a problem in the first place. As I stated before, the
> earlier versions of boost never did this. Is this a bug?
>   
As Boost grows, so do its memory requirements on the compiler. Template 
metaprogramming is especially heavy on memory use, because templates 
instantiate to hundreds, even thousands of types, all of which have a 
bit of typeinfo somewhere.

It could be called a bug - in the same sense that being a memory hog is 
a bug in an application. The problem is that the execution environment 
of a C++ metaprogram is far less well understood than that of a regular 
application.

Sebastian