From: Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: System headers for DJGPP hosted cross compiler
Date: 9 Dec 2002 11:37:06 GMT
Organization: Aachen University of Technology (RWTH)
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Ed Manlove <emanlove AT ieee DOT org> wrote:

> newlib is part of the gcc-2.95.2 tarball. And my experience with the cygwin
> cross compiler for this target is that no other library was used other than
> newlib. 

That's the whole point of newlib, actually.  It provides a C runtime
environment for target platforms that don't have any other, or whose C
runtime you don't want to use for some reason.

> And I have also gathered from this newsgroup that DJGPP is a sense
> does not use newlib that it uses a DJGPP library.  

This is true for the *native* DJGPP compiler (i.e. the binaries you
download at simtel), because their target platform is "Intel PC + DOS
+ DPMI + the DJGPP C runtime".  

You can definitely *not* use the DJGPP libc to replace newlib in the
general case.  Our libc only works for Intel CPU and DOS-compatible
operating systems with a DPMI server in place.

> similar. Yes I see some subtle differences but for the most part I expect
> the configure and make process to follow very similar paths.  

That's a correct expectation, I think, except for those dark corners
where Cygwin, DJGPP, or both of them fail to mimic the native Unix
environment assumed by the GCC build scripts perfectly enough to work
without the occasional glitch.

It takes quite some determination plus a lot of insight to
successfully build a DJGPP-hosted cross compiler, I think.  You should
probably start off by looking at the modifications done to the GCC
sources to build the native DJGPP version.  Chances are you'll need
all of those changes in a cross-build, too.  And then some more, along
the same lines, in those parts of the build process that the native
build doesn't use.  After that, and with some luck, the instructions
given for Cygwin might work for the DJGPP build, too.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.