Re: convert regex.c, strftime.c mktime.c to standard C

[David De La Harpe Golden]

On 20/11/10 15:43, Bruno Haible wrote:

> Emacs uses an Autoconf configure.in.

Not on all platforms, no. e.g. w32 emacs doesn't.

> > > Note that DJGPP is not a supported platform of gnulib.
> >
> > And neither is MinGW, AFAICS, at least not without using MSYS, which
> > is not how Emacs works.
>
> Not true. mingw is supported by about 98% of gnulib (see the documentation
> at http://www.gnu.org/software/gnulib/manual/). And, as you might know,
> there are 3 ways to build binaries for mingw:
>    - using MSYS,
>    - from Cygwin,
>    - cross-compiling from Unix.

You don't need MSYS to build w32 binaries _with_ the mingw toolchain 
(you do need it to build msys and mingw tools and mingwports themselves, 
but that's a different matter to building w32 stuff with mingw).

(cygwin emacs is a also different matter, that's most successfully built 
with cygwin proper of course...)

In fact, the MSYS variants of various command line tools have odd 
handling of some things (sort of like a cut-down cygwin, but compatible 
with neither modern cygwin nor native w32 conventions) compared to the 
more w32-native-ised gnuwin32 tools, say.

I fairly recently slogged through building w32 emacs under WINE and 
mistakenly trying to build with MSYS stuff hanging around cost me a 
couple of days of incomprehensible (for me, as someone not especially 
familiar with or at all a fan of w32) errors.

The MSYS variant tools presently confuse w32 emacs during build (and I 
would guess potentially at run time too).  Now, in principle emacs could 
include some detection of MSYS variant tools and support, but IMO you'd 
be almost getting into a third port of emacs to windows (the line would 
be blurry), i.e.

. cygwin emacs:
  exists
  basically just a unix type port if quirkier than most
  built with cygwin gcc port
  uses autoconf

. w32 emacs
  exists
  native w32 port
  usually built with mingw (remember, used to build with MSVC++ too)
  does not use autoconf

. msys emacs
  hypothetical
  mingwPORT type port
  would build with mingw and msys
  presumably would use msys' autoconf