Re: [Mingw-users] Re: License, -mno-cygwin

[Greg C. <chi...@mi...>]

Jeremy Bettis wrote:
> 
> Ok, I might be missing the point here, but wouldn't it be more MingW-like to
> just make gcc compatible with the Microsoft C++ runtime dll's?  Then it
> wouldn't matter what the libstdc++ license is.

http://www.mingw.org says
  At the basic level, MinGW is a set of include files and import
  libraries that allow a console-mode program to use Microsoft's standard
  C runtime library MSVCRT.DLL (available on all NT systems, and on all
  stock Win9x after the original Windows 95 release (for which it can be
  installed separately)).

C was well standardized when win95 came out. Add some headers (the
standard tells how, and there's a lot of public documentation of ms
extensions) and you can use their C rtl dll.

But here we're talking about C++, which was standardized after win95
came out. I don't think anyone claims to have implemented the entire
C++ standard yet; ms certainly hasn't, and they might not make their
dll freely available.

At any rate, C++ is more complex than C, notably in that the standard
library is implemented partly in code that pretty much has got to be
in a linkable library (like the definition of std::cout) and partly
in templates that have to be in headers (until someone implements the
standard 'export' keyword). The part of the implementation that, for
now at least, is necessarily in headers has to work the same way as
the dll: each needs an intimate knowledge of the other. It would be
hard to write those headers, without relying on their source. The
standard leaves a lot of discretion to implementors: for instance,
strings might be copy on write, or they might not. We'd have to figure
out and follow all their implementation decisions in order to write
headers that complement their rtl. And I suppose we'd need to know
their name-mangling scheme in order to link to their dll; that
might not be public.

While C can put almost 100% of its standard library implementation
in a linkable library, almost 100% of a C++ standard library can
be implemented in headers. I'd rather have those headers be free
software in the gnu sense. If you want headers that are free without
any [L]GPL restrictions, take a look at sgi.com and stlport.org .