I've upgraded at an unstable x86 system the package glibc from 2.16 to 2.17 (gcc-4.7.2). After that apache2 segfaults constantly, re-emerging it and few other packages and even a full revdep-rebuild doesn't help. An "emerge -e world" solved that issue finally. Probably an ewarn should be added to point to such possible situation.
This maybe?: * The `clock_*' suite of functions (declared in <time.h>) is now available directly in the main C library. Previously it was necessary to link with -lrt to use these functions. This change has the effect that a single-threaded program that uses a function such as `clock_gettime' (and is not linked with -lrt) will no longer implicitly load the pthreads library at runtime and so will not suffer the overheads associated with multi-thread support in other code such as the C++ runtime library.
that shouldn't be necessary. what is going wrong needs more debugging. although it's not possible anymore on your system since you rebuilt everything. i doubt the clock_* function move makes any difference as the ABI is unchanged -- you can still find the funcs in -lrt.
(In reply to comment #2) > although it's not possible anymore on your system since you rebuilt It is a user mode linux image were I do chroot into it - and I *do* make backups (although the last is a little bit older). In addition I do have a stable user mode linux image with nearly the same package name list which can be used to test upgrade paths too. The limiting factor is just the CPU and the fact, that all stuff is located at a lame exterbal USB 2.0 drive (from were the Gentoo host system is booted too BTW).