Mercurial > hg > octave-shane > gnulib-hg
view m4/perl.m4 @ 17627:4d899884c95c
m4: fix gl_TIMER_TIME() detection of threads on uClibc
The timer_time.m4 gl_TIMER_TIME function determines which libraries
need to be linked to get access to the timer function, generally -lrt
for Linux systems. On platforms where threads are used, librt
typically uses thread functions from libpthread.
However, the test to determine whether the platform has thread or not
is incorrect: it assumes that if the C library is uClibc, then threads
are not available. This is actually not true: uClibc has configurable
thread support, and when thread support is available, librt calls
libpthread functions.
This is important when static linking is used, because otherwise only
-lrt is used at link time, which fails because librt calls undefined
thread functions. Both -lrt and -lpthread must be passed.
This problem is fixed by making the uClibc thread detection a bit
smarter, thanks to the usage of the __HAS_NO_THREADS__ macro defined
in <bits/uClibc_config.h>, which itself is included by <features.h>.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
author | Thomas Petazzoni <thomas.petazzoni@free-electrons.com> |
---|---|
date | Sat, 22 Feb 2014 00:41:38 +0100 |
parents | 344018b6e5d7 |
children |
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# serial 9 dnl From Jim Meyering. dnl Find a new-enough version of Perl. # Copyright (C) 1998-2001, 2003-2004, 2007, 2009-2014 Free Software Foundation, # Inc. # # This file is free software; the Free Software Foundation # gives unlimited permission to copy and/or distribute it, # with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_PERL], [ dnl FIXME: don't hard-code 5.005 AC_MSG_CHECKING([for perl5.005 or newer]) if test "${PERL+set}" = set; then # 'PERL' is set in the user's environment. candidate_perl_names="$PERL" perl_specified=yes else candidate_perl_names='perl perl5' perl_specified=no fi found=no AC_SUBST([PERL]) PERL="$am_missing_run perl" for perl in $candidate_perl_names; do # Run test in a subshell; some versions of sh will print an error if # an executable is not found, even if stderr is redirected. if ( $perl -e 'require 5.005; use File::Compare' ) > /dev/null 2>&1; then PERL=$perl found=yes break fi done AC_MSG_RESULT([$found]) test $found = no && AC_MSG_WARN([ WARNING: You don't seem to have perl5.005 or newer installed, or you lack a usable version of the Perl File::Compare module. As a result, you may be unable to run a few tests or to regenerate certain files if you modify the sources from which they are derived. ] ) ])