[PATCH 0/1] gdb: discard saved state on error in recursive infcall

[Stephan Rohr <stephan.rohr@intel.com>]

From: "Rohr, Stephan" <stephan.rohr@intel.com>

Hi all,

I came across an issue when we hit a breakpoint in the copy constructor
during an infcall.  GDB runs a nested 'call_function_by_hand (copy_ctor,
...)' that creates the dummy frame.  If we hit a breakpoint inside the
ctor, that call raises an error.  The parent
'call_function_by_hand_dummy' restores the caller's registers.

This works fine until the frame cache is reinitialized, e.g., when
switching inferiors.  In that case, the unwinder cannot reach the dummy
frame anymore and the backtrace command doesn't show the correct frames.

I fixed this by not restoring the caller's state and the inferior status
on errors inside the nested ctor call.  I extended the
'gdb.cp/pass-by-ref-2.exp' testcase to ensure GDB is able to finish the
abandoned infcall.

Regression tested on Ubuntu 24 with the native target.

I appreciate your feedback.

Thanks
Stephan

Rohr, Stephan (1):
  gdb: discard saved state on error in recursive infcall

 gdb/infcall.c                          | 23 +++++++++++++++++++++--
 gdb/testsuite/gdb.cp/pass-by-ref-2.exp | 22 ++++++++++++++++++++++
 2 files changed, 43 insertions(+), 2 deletions(-)

-- 
2.43.0

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