uclibc-boun...@uclibc.org wrote on 15/10/2009 08:41:10: > > On Wed, 2009-10-14 at 09:20 -0700, Cuero Bugot wrote: > .. > > The prb is that I get a segfault when I try to use pthread_create from > > a dynamically linked library. The difference with the above fix use > > case is that I "manually" link the library using dlopen. I initially > > found this prb while trying to use the Lua (www.lua.org) VM with > > uclibc. Lua supports loading extension as so files so it uses dlopen. > > > > I reduced and reproduced the prb with this simple use case: > > > > 2 files (attached): test.c and lib.c > > test.c contains the main() that will load the so file compiled from lib.c. > > lib.c actually creates a thread. (well crashed when trying to create a > > thread). > > Yes. I have had this too for a long time[1] and I also made a > testcase[2] for this. > > I think it hs to do with uclibc having some non-pthread funcs that is > used when pthread is not linked in. So when you dlopen something linked > to pthread, the pthread version of the symbols should have been used, > but they arent, since pthread was not there during first link. > > The apps that this affects is scripting languages lua, ruby and php[3] > together with the sqlite3 binding. I think it also affects cpufreqd. > > The way I have worked around it is to force linking to pthread in the > main binary[4][5][6]. I havent bothered to try fix it in uClibc since we > soon will have NTPL. > > [1] https://bugs.gentoo.org/show_bug.cgi?id=189804
Looked at the bug and if this is the same(I am not convinced) it is a matter of teaching ldso to respect the NO_DELETE flag in the DYNAMIC section. This will be needed for NPTL too if not already impl. I see that modern NPTL has INITFIRST set too, not sure if that is important for pthreads in uClibc though. > [2] http://dev.alpinelinux.org/~ncopa/dl-pthread/ > [3] http://redmine.alpinelinux.org/issues/show/183 > [4] http://git.alpinelinux.org/cgit/aports/commit/? > id=13892e864cacf21636be25149eabcd3e2537f7aa > [5] http://git.alpinelinux.org/cgit/aports/commit/? > id=8853a68804a505e1af90ccbbfc9295551a5d3a6c > [6] http://git.alpinelinux.org/cgit/aports/commit/? > id=9881efaf35fb10a9145a18d71f9af6f019ccab81 > > -nc > > _______________________________________________ > uClibc mailing list > uClibc@uclibc.org > http://lists.busybox.net/mailman/listinfo/uclibc > _______________________________________________ uClibc mailing list uClibc@uclibc.org http://lists.busybox.net/mailman/listinfo/uclibc
