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>

Description:
Finds the most significant bit in an 'unsigned int'.

Files:
lib/integer_length.h
lib/integer_length.c
lib/float+.h
m4/longlong.m4
m4/exponentd.m4

Depends-on:
float

configure.ac:
AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT])
AC_REQUIRE([gl_DOUBLE_EXPONENT_LOCATION])

Makefile.am:
lib_SOURCES += integer_length.c

Include:
"integer_length.h"

License:
LGPLv2+

Maintainer:
Bruno Haible