Re: Patches for Mingw/MSYS

[Charles Wilson]

Ralf Wildenhues wrote:

> a) some setup where config.guess returns *msys* not *mingw*

But here's where you lose me (and remember, I'm a cygwin guy not MSYS or 
MINGW): from what I understand, MSYS is a development environment that 
is basically a fork from cygwin (e.g. there's a cygwin-like DLL 
providing POSIX services).  But the REASON for MSYS to exist at all is 
simply this: to lie.

The idea, I thought, was for MSYS to lie about itself so that you can 
use "normal" unix configury tools which will all be told things by the 
underlying system, and report things to the user, and compile things, 
and link things, AS IF and FOR a "clean" win32 system.  (Contrast this 
with "real" MINGW, which is ONLY a compiler: you can't run "configure" 
because you have no shell, only cmd.exe.  You can't use autoconf because 
you have no m4.  MINGW is only a compiler, a particular port of gcc that 
understands "dos-style" pathnames among other things. [MSYS's gcc is 
slightly different; it is, itself, dependent on the MSYS DLL, which 
provides understanding of both "unix-style" paths but also "dos-style" 
paths -- this latter bit is where it differs from cygwin's DLL].  By 
default MSYS's gcc produces pure-native-windows objects, but it can be 
teased, somehow, into producing MSYS-dll-dependent objects.  Thus, it's 
a cross-compiler(MSYS-host to pure-native-target) that can be teased 
into being a "native"(e.g. MSYS-dependent) compiler)

That is, if I type "./configure && make" in the MSYS shell, what I GET 
should be a MINGW (pure-native-windows) binary.  There is no case where 
I'd actually be ABLE to run libtool on a "MINGW" 'system' -- because 
MINGW is just a compiler, not a 'system'.

Only very rarely (and I don't know how Earnie manages to do this) would 
you actually want to build an "MSYS" binary -- e.g. "make MSYS tell the 
truth".  Basically, only MSYS maintainers would want to do this.

So for the rest of us, I'm not sure there IS a difference between MINGW 
and MSYS -- that is, the ENVIRONMENT is the same: if you're running 
libtool, you've got a shell and m4 and stuff, so you're REALLY running 
under MSYS.  The question is, what is your TARGET: MSYS-dll-dependent, 
or pure-native-windows.

Given the purpose of MSYS, the default target is pure-native-windows 
(what we'd usually call the "cross" target, in that the result runs on a 
pure-native system but the compiler runs under MSYS); the "unusual" 
target is the msys-dependent one (what we'd usually call the "native" 
target, in that the result runs under the same environment as the compiler).

--
Chuck