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PR gdb/11568 is about thread-specific breakpoints being left behind when the corresponding thread exits. Currently: (gdb) b start thread 2 Breakpoint 3 at 0x400614: file thread-specific-bp.c, line 23. (gdb) b end Breakpoint 4 at 0x40061f: file thread-specific-bp.c, line 29. (gdb) c Continuing. [Thread 0x7ffff7fcb700 (LWP 14925) exited] [Switching to Thread 0x7ffff7fcc740 (LWP 14921)] Breakpoint 4, end () at thread-specific-bp.c:29 29 } (gdb) info threads Id Target Id Frame * 1 Thread 0x7ffff7fcc740 (LWP 14921) "thread-specific" end () at thread-specific-bp.c:29 (gdb) info breakpoints Num Type Disp Enb Address What 2 breakpoint keep y 0x0000000000400614 in start at thread-specific-bp.c:23 breakpoint already hit 1 time 3 breakpoint keep y 0x0000000000400614 in start at thread-specific-bp.c:23 thread 2 stop only in thread 2 4 breakpoint keep y 0x000000000040061f in end at thread-specific-bp.c:29 breakpoint already hit 1 time Note that the thread-specific breakpoint 3 stayed around, even though thread 2 is gone. There's no way that breakpoint can trigger again (*), so the PR argues that the breakpoint should just be removed, like local watchpoints. I'm ambivalent on this -- it could be reasonable to disable the breakpoint (kind of like breakpoint in shared library code when the DSO is unloaded), so the user could still use it as visual template for creating other breakpoints (copy/paste command lists, etc.), or we could have a way to change to which thread a breakpoint applies. But, several people pushed this direction, and I don't plan on arguing... (*) - actually, there is ... thread numbers are reset on "run", so the user could do "break foo thread 2", "run", and expect the breakpoint to hit again on the second thread. But given gdb's thread numbering can't really be stable, that'd only work sufficiently well for thread 1, so we'd better call it unsupported. So with the patch, whenever a thread is deleted from GDB's list, GDB goes through the thread-specific breakpoints and deletes corresponding breakpoints. Since this is user-visible, GDB prints out: Thread-specific breakpoint 3 deleted - thread 2 is gone. And of course, we end up with: (gdb) info breakpoints Num Type Disp Enb Address What 2 breakpoint keep y 0x0000000000400614 in start at thread-specific-bp.c:23 breakpoint already hit 1 time 4 breakpoint keep y 0x000000000040061f in end at thread-specific-bp.c:29 breakpoint already hit 1 time 2013-09-17 Muhammad Waqas <mwaqas@codesourcery.com> Pedro Alves <palves@redhat.com> PR gdb/11568 * breakpoint.c (remove_threaded_breakpoints): New function. (_initialize_breakpoint): Attach remove_threaded_breakpoints as thread_exit observer. 2013-09-17 Muhammad Waqas <mwaqas@codesourccery.com> Jan Kratochvil <jan.kartochvil@redhat.com> Pedro Alves <palves@redhat.com> PR gdb/11568 * gdb.thread/thread-specific-bp.c: New file. * gdb.thread/thread-specific-bp.exp: New file. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
readline | ||
sim | ||
texinfo | ||
.cvsignore | ||
.gitignore | ||
ChangeLog | ||
compile | ||
config-ml.in | ||
config.guess | ||
config.rpath | ||
config.sub | ||
configure | ||
configure.ac | ||
COPYING | ||
COPYING3 | ||
COPYING3.LIB | ||
COPYING.LIB | ||
COPYING.LIBGLOSS | ||
COPYING.NEWLIB | ||
depcomp | ||
djunpack.bat | ||
install-sh | ||
libtool.m4 | ||
lt~obsolete.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
MAINTAINERS | ||
Makefile.def | ||
Makefile.in | ||
Makefile.tpl | ||
makefile.vms | ||
missing | ||
mkdep | ||
mkinstalldirs | ||
move-if-change | ||
README | ||
README-maintainer-mode | ||
setup.com | ||
src-release | ||
symlink-tree | ||
ylwrap |
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.