Re: alloca redeclaration warning on MinGW

[Paul Eggert]

Hrvoje Niksic <address@hidden> writes:

> Paul Eggert <address@hidden> writes:
>> This doesn't look right to me, because if _MSC_VER is defined, it
>> includes <malloc.h> without the "# define alloca _alloca" line that
>> other people seem to have needed.
>
> I haven't needed that line in Wget.  Maybe it was needed in older
> versions of Visual C?

More likely it's the other way around.
<http://msdn2.microsoft.com/library/wb1s57t5(en-us,vs.80).aspx>
indicates that Visual Studio 2005 doesn't define alloca.  And
<http://sourceforge.net/mailarchive/forum.php?forum_id=5120&max_rows=25&style=nested&viewmonth=200403>
suggests that a #define for alloca was removed from mingw last year.

>> Also, what is the difference between _MSC_VER, __BORLANDC__, and
>> __MINGW32__?  Are these different compilers?
>
> They are different compilers.  What they have in common is that they
> (these days) run in the Win32 environment,

Is there a single symbol that all three define?  I'd rather not have
to maintain a list of Microsoft Windows 32 compilers.  (And please
don't call it "Win32", as it's not a win.  A better name is "32-bit
Windows operating environment", or "Woe32".)

For example, <http://megapov.inetart.net/manual-1.2/binaries.html>
talks about __BORLANDC__, __DJGPP__, __MINGW32__, __CYGWIN__, __DMC__,
and __WATCOMC__.  I doubt whether even this list is exhaustive.  Nor
do I know which of these compilers require <malloc.h>.

This sounds like a job for an Autoconf test rather than for trying to
guess from predefined macros.  But someone with some Woe32 expertise
will be needed to write the test.