Re: Debugging and NPTL
Daniel Jacobowitz <[email protected]> Mon, 17 May 2004 17:00:40 -0400
| Newsgroups | gmane.comp.lib.phil |
|---|---|
| Message-ID | <[email protected]> |
On Mon, May 17, 2004 at 04:59:30PM -0400, Ali Ijaz Sheikh wrote: > Quoting Daniel Jacobowitz <[email protected]>: > > > On Mon, May 17, 2004 at 03:11:45PM -0400, Ali Ijaz Sheikh wrote: > > > > > > Hi, > > > > > > I have recently started seeing some problems with debugging of > > multithreaded > > > applications with NPTL on 2.6 series kernels. It seems that GDB is no > > longer > > > being informed of the events occurring in the child threads because > > > create_thread (nptl/sysdeps/pthread/create_thread.c) routine does not pass > > the > > > CLONE_PTRACE flag to the clone system call. For example, if the child > > thread > > > gets a SEGV, the whole thread group is terminated without GDB ever being > > told. > > > > > > When creating a thread in a thread group that is being ptraced, shouldn't > > the > > > child thread be created with a CLONE_PTRACE? It this a nptl bug? Or is > > this > > > GDB's fault? > > > > > > A simple program that creates a thread and does raise(SIGSEGV) in the child > > > thread can be used to reproduce this problem. Try running that in gdb. > > > > No, it should not be using CLONE_PTRACE. You didn't say what version > > of GDB you were using; you may want to try a newer one. > > > > -- > > Daniel Jacobowitz > > > > I have tried this with GDB 6.0 and 6.1. GDB 6.1 should support NPTL out of the box. -- Daniel Jacobowitz