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c++/2488: "next" command in a function that throws a C++ exception causes GDB to lose control of the inferior
- From: pmuldoon at redht dot com
- To: gdb-gnats at sources dot redhat dot com
- Date: 1 Aug 2008 15:13:59 -0000
- Subject: c++/2488: "next" command in a function that throws a C++ exception causes GDB to lose control of the inferior
- Reply-to: pmuldoon at redht dot com
>Number: 2488
>Category: c++
>Synopsis: "next" command in a function that throws a C++ exception causes GDB to lose control of the inferior
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Fri Aug 01 15:18:02 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator: pmuldoon@redht.com
>Release: 6..8
>Organization:
>Environment:
Linux
>Description:
Run the next command in a function that throws a C++ exception. The inferior is not stopped as described in next command help. The inferior continues until program exit, or an unrelated breakpoint triggers. Expectation is that the inferior should either stop in the first local variable destructor (if there is one) or in the matching catch exception handler (if there is one).
>How-To-Repeat:
The included test-case shows the behaviour. Step to func1, then run "next" from that function. The program will exit. It should stop in the the catch exception handler in this case.
>Fix:
Looking at next_command() it installed four momentary breakpoints (longjmp/siglongjmp/_longjnp/_siglongjmp) and resumes the inferior. C++ Exception handling does not use this method, but instead relies on dwarf register annotations and unwinding the stack and type-checking exception handlers. next command needs to account for methods other than longjmp.
>Release-Note:
>Audit-Trail:
>Unformatted:
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