view m4/sched_h.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
line wrap: on
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# sched_h.m4 serial 6
dnl Copyright (C) 2008-2013 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 Written by Bruno Haible.

AC_DEFUN([gl_SCHED_H],
[
  AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([[
       #include <sched.h>
       struct sched_param a;
       int b[] = { SCHED_FIFO, SCHED_RR, SCHED_OTHER };
       pid_t t1;
     ]])],
    [SCHED_H=''],
    [SCHED_H='sched.h'

     gl_CHECK_NEXT_HEADERS([sched.h])

     if test $ac_cv_header_sched_h = yes; then
       HAVE_SCHED_H=1
     else
       HAVE_SCHED_H=0
     fi
     AC_SUBST([HAVE_SCHED_H])

     AC_CHECK_TYPE([struct sched_param],
       [HAVE_STRUCT_SCHED_PARAM=1], [HAVE_STRUCT_SCHED_PARAM=0],
       [#include <sched.h>])
     AC_SUBST([HAVE_STRUCT_SCHED_PARAM])

     dnl Ensure the type pid_t gets defined.
     AC_REQUIRE([AC_TYPE_PID_T])
    ])
  AC_SUBST([SCHED_H])
  AM_CONDITIONAL([GL_GENERATE_SCHED_H], [test -n "$SCHED_H"])
])