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A finish breakpoint is a temporary breakpoint set at the return address of
a frame, based on the finish
command. gdb.FinishBreakpoint
extends gdb.Breakpoint
. The underlying breakpoint will be disabled
and deleted when the execution will run out of the breakpoint scope (i.e.
Breakpoint.stop
or FinishBreakpoint.out_of_scope
triggered).
Finish breakpoints are thread specific and must be create with the right
thread selected.
Create a finish breakpoint at the return address of the
gdb.Frame
object frame. If frame is not provided, this defaults to the newest frame. The optional internal argument allows the breakpoint to become invisible to the user. See Breakpoints In Python, for further details about this argument.
In some circumstances (e.g.
longjmp
, C++ exceptions, gdbreturn
command, ...), a function may not properly terminate, and thus never hit the finish breakpoint. When gdb notices such a situation, theout_of_scope
callback will be triggered.You may want to sub-class
gdb.FinishBreakpoint
and override this method:class MyFinishBreakpoint (gdb.FinishBreakpoint) def stop (self): print "normal finish" return True def out_of_scope (): print "abnormal finish"
When gdb is stopped at a finish breakpoint and the frame used to build the
gdb.FinishBreakpoint
object had debug symbols, this attribute will contain agdb.Value
object corresponding to the return value of the function. The value will beNone
if the function return type isvoid
or if the return value was not computable. This attribute is not writable.