3.0.0 configure failure (bug in autoconf 2.10?)

3.0.0 configure failure (bug in autoconf 2.10?)

[Bart Schaefer]

Linux 1.3.15, gcc 2.7.0, ELF.

....
checking for tcsetpgrp... yes
checking for tcgetattr... yes
checking for strstr... yes
checking for lstat... no
checking for getlogin... yes
checking for setpgid... yes
....

The message from config.log is:
/tmp/cca194791.o(.text+0x14): undefined reference to `lstat'

The problem seems to be in the AC_CHECK_FUNCS macro.  Zsh's configure,
which says it is from autoconf 2.10, produces a conftest.c containing
the equivalent of:

char lstat();
int t() {
 lstat();
 return 0;
}

If I look at a different software package whose configure was generated by
autoconf 1.11, the code is:

int t() {
 extern char lstat(); lstat();
 return 0;
}

This latter compiles successfully and thus defines HAVE_LSTAT.

So just exactly who is wrong here?  autoconf?  gcc 2.7.0?

In any case, I suggest the following change to glob.c, just to prevent the
(@) glob modifier from producing wildly inaccurate results when configure
makes this kind of error.

--- Src/glob.c.0	Sat Jul 27 13:24:36 1996
+++ Src/glob.c	Mon Aug 19 22:39:47 1996
@@ -212,7 +212,7 @@
 			/* Toggle matching of symbolic links */
 			sense ^= 2;
 			break;
-#ifdef S_IFLNK
+#if defined(S_IFLNK) && defined(HAVE_LSTAT)
 		    case '@':
 			/* Match symbolic links */
 			func = qualmode;

-- 
Bart Schaefer                             Brass Lantern Enterprises
http://www.well.com/user/barts            http://www.nbn.com/people/lantern

New male in /home/schaefer:
>N  2 Justin William Schaefer  Sat May 11 03:43  53/4040  "Happy Birthday"

Re: 3.0.0 configure failure (bug in autoconf 2.10?)

[Bob Glickstein]

> So just exactly who is wrong here?  autoconf?  gcc 2.7.0?

It could be either.  What causes the autoconf 2.10 version of the
lstat test to fail?  (Find out by looking in config.log after running
configure.)

Of course, gcc 2.7.0 is three versions out of date; the current one is
2.7.2.1.

Re: 3.0.0 configure failure (bug in autoconf 2.10?)

[Bart Schaefer]

On Aug 20,  8:16am, Bob Glickstein wrote:
} Subject: Re: 3.0.0 configure failure (bug in autoconf 2.10?)
}
} > So just exactly who is wrong here?  autoconf?  gcc 2.7.0?
} 
} It could be either.  What causes the autoconf 2.10 version of the
} lstat test to fail?  (Find out by looking in config.log after running
} configure.)

I included that in the original message.

/tmp/cca194791.o(.text+0x14): undefined reference to `lstat'

That's all, nothing else.  I just figured out why it fails, though:  lstat
is an *inline function only* that expands to a call to _lxstat.  If you
don't include <sys/stat.h> (which the conftest does not), you can't detect
lstat.

Perhaps AC_CHECK_FUNCS is the wrong way to test for lstat?  I don't have
autoconf 2.10 installed to check the info for a more specific AC_* test.

-- 
Bart Schaefer                             Brass Lantern Enterprises
http://www.well.com/user/barts            http://www.nbn.com/people/lantern

New male in /home/schaefer:
>N  2 Justin William Schaefer  Sat May 11 03:43  53/4040  "Happy Birthday"

Re: 3.0.0 configure failure (bug in autoconf 2.10?)

[Bob Glickstein]

> Perhaps AC_CHECK_FUNCS is the wrong way to test for lstat?  I don't
> have autoconf 2.10 installed to check the info for a more specific
> AC_* test.

Well, there's AC_PROG_LN_S, which tests whether "ln -s" works; that
should indirectly indicate the availability of lstat().  But
AC_CHECK_FUNCS should work, and I consider it a bug in autoconf that
it doesn't.  I suggest sending a bug report to
bug-gnu-utils@prep.ai.mit.edu.

Re: 3.0.0 configure failure (bug in autoconf 2.10?)

[Zoltan Hidvegi]

> Linux 1.3.15, gcc 2.7.0, ELF.
[...]
> checking for lstat... no
[...]

This is an autoconf bug but only happens with obsolate libc versions like
5.0.9 which used some preprocessor hacks on lstat because of some
incompatible kernel changes made sometime between linux-1.0 and linux-1.2.
Recent libc's use elf hacks to solve the problem.  You should better
upgrade your libc and your kernel.  It is also mentioned in Etc/MACHINES.

Zoltan