Mercurial > gnulib
view m4/nonblocking.m4 @ 37246:5cfb3a67238d
regex: avoid glibc deadlock during configure
glibc has a known bug where certain corruptions of the heap can
cause malloc to default to printing a debug message that includes
a backtrace, but the act of getting the backtrace uses dlopen
which in turn calls into malloc, causing a recursive lock ending
in deadlock. Thus, when configure is probing for a known glibc
heap corruption bug, the overall configure would hang.
The solution suggested by glibc developers is to force malloc
to quit printing debug messages, which avoids recursive malloc.
* m4/regex.m4 (gl_REGEX): Avoid recursive malloc deadlock when
glibc bug 15078 in turn triggers bug 16159.
Reported by Michal Privoznik.
Signed-off-by: Eric Blake <eblake@redhat.com>
author | Eric Blake <eblake@redhat.com> |
---|---|
date | Tue, 03 Dec 2013 10:34:13 -0700 |
parents | c741bc27922a |
children | 344018b6e5d7 |
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# nonblocking.m4 serial 2 dnl Copyright (C) 2011-2013 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. dnl Tests whether non-blocking I/O is natively supported by read(), write(). dnl Sets gl_cv_have_nonblocking. dnl Also tests whether open() supports O_NONBLOCK. dnl Sets gl_cv_have_open_O_NONBLOCK. AC_DEFUN([gl_NONBLOCKING_IO], [ dnl Use AC_REQUIRE here, so that the default behavior below is expanded dnl once only, before all statements that occur in other macros. AC_REQUIRE([gl_NONBLOCKING_IO_BODY]) ]) AC_DEFUN([gl_NONBLOCKING_IO_BODY], [ AC_REQUIRE([AC_CANONICAL_HOST]) case "$host_os" in mingw*) gl_cv_have_nonblocking=no ;; *) gl_cv_have_nonblocking=yes ;; esac case "$host_os" in mingw*) gl_cv_have_open_O_NONBLOCK=no ;; *) gl_cv_have_open_O_NONBLOCK=yes ;; esac ])