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Re: [patch/rfc,6.1?] Use right frame ID in step_over_function


The bug apepars when trying to step over nested shared library non-debug
info functions (making sense?).


No, not really.  Could you give us a testcase?  What platform have you
seen this behavior on?

PPC/NetBSD.


On Sat, Feb 28, 2004 at 11:33:51PM -0500, Andrew Cagney wrote:

Hello,

This goes into the "how did it ever work" category. The idea of step_over_function is that it:

- finds the caller's resume address
- finds the caller's frame ID

and then sets a breakpoint for that caller instance of the function. The current code:

- finds the caller's resume address
- finds the _callee_ frame ID

and then uses that to set the breakpoint. Now that is plain weird! It only works because either:

- the step_frame_id patches up the bug

- the values match as GDB is using the inner-most, rather than outer-most frame address as part of the frame ID

The NetBSD/PPC case, the old code does this: /* NOTE: cagney/2002-04-14: The ->frame points to the inner-most address of the current frame. Things might be easier if the ->frame pointed to the outer-most address of the frame. In the mean time, the address of the prev frame is used as the base address of this frame. */

The bug apepars when trying to step over nested shared library non-debug info functions (making sense?).

So I suspect it applied to all PPC, just that NetBSD's are a bit wierd.


Andrew



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