Robert P. J. DAY says:
According to Mike Frysinger, this patch was removed from Gentoo in the
2.3.x series and didn't seem to cause any adverse effects. So toss it
from the patch directories for glibc 2.5 and up.
1 --- gcc-4.1.2.orig/boehm-gc/include/gc.h 2005-01-02 04:35:57.000000000 +0100
2 +++ gcc-4.1.2/boehm-gc/include/gc.h 2007-03-04 23:33:07.000000000 +0100
6 # if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 || __GLIBC__ > 2) \
7 - && !defined(__ia64__)
8 + && !defined(__ia64__) && !defined(__UCLIBC__)
9 # ifndef GC_HAVE_BUILTIN_BACKTRACE
10 # define GC_HAVE_BUILTIN_BACKTRACE