Re: [bug-gnulib] typo in extensions.m4

[Bruno Haible]

Jim Meyering wrote:
> I've just checked this in:
>
> @@ -19,7 +19,7 @@ AC_DEFUN([gl_USE_SYSTEM_EXTENSIONS], [
>
>    AH_VERBATIM([__EXTENSIONS__],
>  [/* Enable extensions on Solaris.  */
> -#ifndef __EXTENSIONS__
> +#ifdef __EXTENSIONS__
>  # undef __EXTENSIONS__
>  #endif])
>    AC_DEFINE([__EXTENSIONS__])

I don't think this is right. The purpose of the macro is to ensure that
__EXTENSIONS__ is defined. The "undef" line gets turned into a "define" line
by config.status. The purpose of the #ifndef line was to avoid
"macro redefined" warnings from gcc.

The way you changed it now, the macro will do nothing if __EXTENSIONS__
is not defined, and produce a warning if __EXTENSIONS__ is already defined.

Bruno