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From: "pedro at codesourcery dot com" <sourceware-bugzilla@sourceware.org> To: gdb-prs@sourceware.org Subject: [Bug breakpoints/8236] Watchpoints in multi-thread programs Date: Tue, 17 Nov 2009 21:28:00 -0000 [thread overview] Message-ID: <20091117212842.20445.qmail@sourceware.org> (raw) In-Reply-To: <20030307184801.8236.ebs@ebshome.net> ------- Additional Comments From pedro at codesourcery dot com 2009-11-17 21:28 ------- GDB supports hardware watchpoints on multi-thread programs nowadays (with a few gotchas). The text in question seems to have been replaced in the manual. @cindex watchpoints and threads @cindex threads and watchpoints In multi-threaded programs, watchpoints will detect changes to the watched expression from every thread. @quotation @emph{Warning:} In multi-threaded programs, software watchpoints have only limited usefulness. If @value{GDBN} creates a software watchpoint, it can only watch the value of an expression @emph{in a single thread}. If you are confident that the expression can only change due to the current thread's activity (and if you are also confident that no other thread can become current), then you can use software watchpoints as usual. However, @value{GDBN} may not notice when a non-current thread's activity changes the expression. (Hardware watchpoints, in contrast, watch an expression in all threads.) @end quotation The issue with software watchpoints is that with the default scheduler locking of off, when gdb steps a thread for a watchpoint, other threads run free for a bit. This could be fixed by stepping all threads simultaneously. Needs target_resume interface changes to make it work in all-stop. -- http://sourceware.org/bugzilla/show_bug.cgi?id=8236 ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is.
parent reply other threads:[~2009-11-17 21:28 UTC|newest] Thread overview: expand[flat|nested] mbox.gz Atom feed [parent not found: <20030307184801.8236.ebs@ebshome.net>]
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