Mercurial > gnulib
view m4/tanf.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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# tanf.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. AC_DEFUN([gl_FUNC_TANF], [ AC_REQUIRE([gl_MATH_H_DEFAULTS]) AC_REQUIRE([gl_FUNC_TAN]) dnl Persuade glibc <math.h> to declare tanf(). AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) dnl Test whether tanf() exists. Assume that tanf(), if it exists, is dnl defined in the same library as tan(). save_LIBS="$LIBS" LIBS="$LIBS $TAN_LIBM" AC_CHECK_FUNCS([tanf]) LIBS="$save_LIBS" if test $ac_cv_func_tanf = yes; then TANF_LIBM="$TAN_LIBM" else HAVE_TANF=0 TANF_LIBM="$TAN_LIBM" fi AC_SUBST([TANF_LIBM]) ])