Autoconf v2.13 bug report (Solaris getmntent is in libc, not libgen)

[john.clark@experian.com]

While trying to compile libgtop-1.1.0, I noticed that libtool was complaining
about libgen.  Following a hunch, I looked at config.log, which revealed that
configure had decided the function "getmntent" was in -lgen, because the
compiler did not produce an error.

getmntent(3C) is in libc, not libgen, on Solaris.  Configure guesses incorrectly
because it does not try including no libraries until the last test (if I
understand the macros correctly, which I am not at all sure I do).  There IS a
libgen.a on Solaris (in /usr/ccs/lib), so the compile with -lgen succeeds, and
configure is fooled.

The relevant macro appears in acspecific.m4 in the autoconf distribution.
Although I do not understand the m4 stuff sufficiently to generate a patch, it
seems to me that you should be able to avoid this problem by moving the test
with no libraries before the test with -lsun, -lseq & -lgen.  (If you follow
me.)

Incidentally, I checked this on Solaris 2.5.1, 2.6 and 7, and getmntent is in
libc on all three.

Thanks!

John Clark
Unix System Administrator
Experian Database Marketing Solutions, Inc.