Documenting tools necessary for GCC [draft]

[Zack Weinberg]

"Joseph S. Myers" <jsm28@cam.ac.uk> writes:

> POSIX make is fairly useless, but the POSIX shell specification
> essentially documented ksh (which is what e.g. Solaris uses as
> /usr/xpg4/bin/sh).  It is a usable environment for writing portable shell
> scripts and far better to specify that than to attempt to support
> derivatives of the original Bourne shell.  The POSIX specification of the
> shell is also much clearer than most other documents that attempt to
> explain the Unix shell.

I mostly agree, but there are still areas which can cause trouble.
For instance, there is nothing in POSIX saying that IFS must be set to
<space><tab><newline> on startup, ignoring any value in the
environment, but all our configure scripts break if the shell doesn't
do that.  (Autoconf 2.5x may have fixed this.)  This is *not* a
hypothetical problem - the Debian ash maintainer at one point tried to
have it be unset on startup, relented only after a ferocious argument,
and insisted on reserving the right to change it again in the future.

Another good example is the insane removal of support for obsolete
command line syntax in the 2001 revision, for things like "sort +1".
And didn't someone say upthread that AIX /bin/ksh had performance
problems with libstdc++-v3/configure?

zw