Re: win32 compiler test V3a

[Akim Demaille <akim at epita dot fr>]

| Hopefully this is it (barring a rename on the high level interface.
| I missed the CPPFLAGS in the last version..
| If you're code is portable this is effective with a simple
| AC_API_WIN32

You should really read the CVS Autoconf documentation.  Your quotation
is dangerous at some points, and there are a few suggestions in there
on how to unobfuscate M4 code.

| dnl COMPILER WIN32 support ====================================
| AC_DEFUN(AC_PROG_CC_WIN32, [
| dnl figure out how to run CC with access to the win32 api if present
| dnl configure that as the CC program, 
| dnl WIN32 may be present with WINE, under cygwin, or under mingw,
| dnl or cross compilers targeting those same three targets.
| dnl as it happens, I can only test cygwin, so extra input here will be appreciated
| dnl send bug reports to Robert Collins <rbtcollins@hotmail.com>
| 
| dnl logic: is CC already configured? if not, call AC_PROG_CC.
| dnl if so - try it. If that doesn't work ,try -mwin32. If that doesn't work, fail
| dnl
| dnl 2001-03-15 - Changed from yes/no to true/false -suggested by Lars J Aas<larsa@sim.no>
| dnl 	* Change true to : - suggest by Alexandre Oliva <oliva@lsd.ic.unicamp.br>
| dnl	* changed layout on the basis of autoconf mailing list:
| dnl		there are now two interfaces, a language specific one which sets
| dnl		or clears WIN32 && WIN32FLAGS as appropriate
| dnl

Move the comments out of the macro, use `#', not dnl, quote the name
being defined.

| AC_REQUIRE([AC_PROG_CC])

dnl at the end

| echo $ECHO_N "checking how to access the Win32 API..." >&6

This is wrong, use the AC_FD_* if you need to, otherwise you certainly
mean AC_MSG_*

| WIN32FLAGS=
| AC_TRY_COMPILE(,[#ifndef WIN32
| #ifndef _WIN32
| #error WIN32 or _WIN32 not defined
| #endif
| #endif],

#error is suspected to cause problems, although I don't recall having
seen it happen.  Please indent cpp directives.

| [
| dnl found windows.h with the current config.
| echo "${ECHO_T}Win32 API found by default" >&6
| ], [

You must not use ECHO_N, you are breaking the abstraction layers :)

| dnl try -mwin32
| save_cc="$ac_compile"

You break out of the Autoconf name space: use ac_compile_save for
readability. 

| dnl we change CC so config.log looks correct
| save_CC="$CC"
| ac_compile="$ac_compile -mwin32"
| CC="$CC -mwin32"
| AC_TRY_COMPILE(,[#ifndef WIN32
| #ifndef _WIN32
| #error WIN32 or _WIN32 not defined
| #endif
| #endif], [
| dnl found windows.h using -mwin32
| echo "${ECHO_T}Win32 API found via -mwin32" >&6
| ac_compile="$save_cc"
| CC="$save_CC"
| WIN32FLAGS="-mwin32"
| ], [
| ac_compile="$save_cc"
| CC="$save_CC"
| echo "${ECHO_T}Win32 API Not found" >&6
| ])
| ])
| 
| AC_PROVIDE([$0])

Huh?  Don't, AC_DEFUN did for you.

| AC_DEFUN(AC_PROG_CXX_WIN32, [

Same comments.

| AC_DEFUN(AC_API_WIN32, [
| dnl high level interface for finding out compiler support for win32.
| 
| AC_LANG_CASE([C],	AC_PROG_CC_WIN32 [CFLAGS="$WIN32FLAGS $CFLAGS"
| CPPFLAGS="$WIN32FLAGS $CPPFLAGS"],
|              [C++],	AC_PROG_CXX_WIN32 [CXXFLAGS="$WIN32FLAGS $CXXFLAGS"
| CPPFLAGS="$WIN32FLAGS $CPPFLAGS"],
|              [echo "No macro support for WIN32 with $_AC_LANG"
|                 exit 1])
| ])

Use AC_FATAL.  Quote the exec parts.  And in fact, just factor
AC_PROG_CXX_WIN32 as an AC_REQUIRE of this macros.