f169cfdc08
When multiple threads within a process wish to report STOPPED events from wait(), the kernel picks one thread event as the thread event to report. The chosen thread event is retrieved via PT_LWPINFO by passing the process ID as the request pid. If multiple events are pending, then the subsequent wait() after resuming a process will report another STOPPED event after resuming the process to handle the next thread event and so on. A single thread event is cleared as a side effect of resuming the process with PT_CONTINUE, PT_STEP, etc. In older kernels, however, the request pid was used to select which thread's event was cleared rather than always clearing the event that was just reported. To avoid clearing the event of the wrong LWP, always pass the process ID instead of an LWP ID to PT_CONTINUE or PT_SYSCALL. In the case of stepping, the process ID cannot be used with PT_STEP since it would step the thread that reported an event which may not be the thread indicated by PTID. For stepping, use PT_SETSTEP to enable stepping on the desired thread before resuming the process via PT_CONTINUE instead of using PT_STEP. This manifested as a failure in the gdb.threads/continue-pending-status.exp test. Specifically, if thread 2 reported a breakpoint and the test thus switched to thread 3 before continuing, thread 3's event (if any) was discarded and thread 2's breakpoint remained pending and was reported a second time as a duplicate event. As a result, the PC was decremented twice for the same breakpoint resulting in an illegal instruction fault on x86. gdb/ChangeLog: * fbsd-nat.c (fbsd_resume): Use PT_SETSTEP for stepping and a wildcard process pid for super_resume for kernels with a specific bug. |
||
|---|---|---|
| bfd | ||
| binutils | ||
| config | ||
| cpu | ||
| elfcpp | ||
| etc | ||
| gas | ||
| gdb | ||
| gold | ||
| gprof | ||
| include | ||
| intl | ||
| ld | ||
| libdecnumber | ||
| libiberty | ||
| opcodes | ||
| readline | ||
| sim | ||
| texinfo | ||
| zlib | ||
| .cvsignore | ||
| .gitattributes | ||
| .gitignore | ||
| COPYING | ||
| COPYING.LIB | ||
| COPYING.LIBGLOSS | ||
| COPYING.NEWLIB | ||
| COPYING3 | ||
| COPYING3.LIB | ||
| ChangeLog | ||
| MAINTAINERS | ||
| Makefile.def | ||
| Makefile.in | ||
| Makefile.tpl | ||
| README | ||
| README-maintainer-mode | ||
| compile | ||
| config-ml.in | ||
| config.guess | ||
| config.rpath | ||
| config.sub | ||
| configure | ||
| configure.ac | ||
| depcomp | ||
| djunpack.bat | ||
| install-sh | ||
| libtool.m4 | ||
| ltgcc.m4 | ||
| ltmain.sh | ||
| ltoptions.m4 | ||
| ltsugar.m4 | ||
| ltversion.m4 | ||
| lt~obsolete.m4 | ||
| makefile.vms | ||
| missing | ||
| mkdep | ||
| mkinstalldirs | ||
| move-if-change | ||
| setup.com | ||
| src-release.sh | ||
| symlink-tree | ||
| ylwrap | ||
README
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.