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:
ilogbl() function: get exponent as integer.

Files:
lib/ilogbl.c
lib/ilogb.c
m4/ilogbl.m4
m4/mathfunc.m4

Depends-on:
math
extensions
ilogb           [test $HAVE_ILOGBL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
isfinite        [test $HAVE_ILOGBL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
frexpl          [test $HAVE_ILOGBL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
isnanl          [test $HAVE_ILOGBL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]

configure.ac:
gl_FUNC_ILOGBL
if test $HAVE_ILOGBL = 0; then
  AC_LIBOBJ([ilogbl])
fi
gl_MATH_MODULE_INDICATOR([ilogbl])

Makefile.am:

Include:
<math.h>

Link:
$(ILOGBL_LIBM)

License:
LGPL

Maintainer:
Bruno Haible