Re: [Boost-users] [Regex] Source-only link error in MSVC

Subject: Re: [Boost-users] [Regex] Source-only link error in MSVC
From: John Maddock (john_at_[hidden])
Date: 2009-05-19 04:42:57

> I wrote the following code:
>
>    #define BOOST_REGEX_SOURCE
>    #include <boost/regex.hpp>
>
>    int main()
>    {
>        boost::regex r("a");
>        return 0;
>    }
>
> Everything compiles, but linking fails with the above error.  The
> same error results if I try this:
>
>     boost::regex * p = new boost::regex("a");
>
> Or if I use boost::wregex, or
> boost::basic_regex<char,boost::regex_traits<char,boost::w32_regex_tr
> aits<char>>>, etc.  Also, the outcome is the same whether I #define
> BOOST_REGEX_SOURCE, BOOST_REGEX_NO_LIB, or BOOST_ALL_NO_LIB, and
> whether I define them in the .cpp or in Project -> Properties,
> Configuration Properties -> C/C++ -> Preprocessor: Preprocessor
> Definitions, and whether I #include <boost/regex.hpp> or
> <boost/regex/v4/regex.hpp>, and whether I use Debug or Release
> configuration.
>
> If I put a #error by the do_assign implementation in
> boost/regex/v4/basic_regex.hpp, it gets hit, so the implementation
> isn't being #if'ed away somehow.
>
> It will build successfully if, in the .cpp file in which main()
> resides, I write an implementation and replace all the template
> arguments, but besides being vulgar, this kludge also fails (with
> compiler errors) if I try to copy-and-paste the full implementation
> from basic_regex.hpp, so it's untenable as a workaround.
>
> In a post from 2006, John wrote, "if you are doing something, umm,
> strange, and you can't track down the cause of the error, you can
> always just add the regex source directly to your application," but
> I've not seen this successfully demonstrated in Visual C++.  I'm
> just looking for an absolutely parsimonious way to add Boost Regex
> to a VC++ project.

Well, you need to do what I said, not what you did ;-)

Take all the .cpp files in libs/regex/src and add them to your console 
project's source, build and voila, it should all work.

BTW use BOOST_REGEX_NO_LIB not BOOST_REGEX_SOURCE in your source files, as 
the latter is for private regex use only and most certainly does not do what 
you think it does.

In point of fact I do this all the time, so it definitely does work.

HTH, John.