Add safe sem_post handler and glibc-2.21 expected output for helgrind tests.
This fixes the tc18 and tc20 testcases.
On some bad semaphores glibc now might just abort, we catch the SIGABRT
and turn it into a EINVAL. The program will see this, but the helgrind
wrapper won't. Which works for tc18 since there is an alternate exp file
with that result (silent bad sem_post). We add a similar alternative exp
file for tc21.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15620 a5019735-40e9-0310-863c-91ae7b9d1cf9
5 files changed