search for: _unwind_forcedunwind

Hi Duncan, On Sep 27, 2011, at 7:58, Duncan Sands wrote: > Hi Bill, > >>>> I'm looking at the docs, and while it refers to a "catch-all" clause, >>> >>> hopefully Bill will get rid of the first reference to "catch-all" since >>> that section is inaccurate. >>> >> I *think* this is now correct. Please check. :)

...a cleanup is not considered to be a handler. If the C++ unwinder sees the call to _Unwind_RaiseException return like this then it terminates the program. Cleanups will therefore not have been run. The Ada unwinder behaves differently. If it the call to _Unwind_RaiseException returns then it calls _Unwind_ForcedUnwind which runs all the cleanups. The program is then terminated. In the more common situation of the unwinder seeing a handler somewhere up the stack it doesn't return and moves on to phase 2 as you described; but your description doesn't apply to the case in which there are only cleanups....

On Sep 27, 2011, at 4:58 AM, Duncan Sands wrote: > Hi Bill, > >>>> I'm looking at the docs, and while it refers to a "catch-all" clause, >>> >>> hopefully Bill will get rid of the first reference to "catch-all" since >>> that section is inaccurate. >>> >> I *think* this is now correct. Please check. :) >

...n, if the search phase discovers that nothing matches the exception except for cleanups all the way up the stack, then the call to _Unwind_RaiseException returns (otherwise control branches to the landing pad that matched the exception). If you want cleanups to be run anyway, then you need to call _Unwind_ForcedUnwind if _Unwind_RaiseException returns. This is in contrast to what happens if there is a catch-all: the call to _Unwind_RaiseException will see that the exception matches the catch-all (because the personality function says so) and it will cause execution to resume at the corresponding landing pad....

I'm looking at the docs, and while it refers to a "catch-all" clause, it doesn't describe how to construct one. In the old scheme, a selector value of 0 was used. What's the corresponding technique for the new scheme? Do I need to update my personality function to handle catch-alls (it wasn't needed in the previous scheme)? -- -- Talin -------------- next part

...nwind_Resume(_Unwind_Exception *exception_object) { ^ C:/Users/clang/libunwind/include\unwind.h:175:13: note: previous declaration is here extern void _Unwind_Resume(_Unwind_Exception *exception_object); ^ C:/Users/clang/libunwind/src/UnwindLevel1.c:408:1: warning: redeclaration of '_Unwind_ForcedUnwind' should not add 'dllexport' attribute [-Wdll-attribute-on-redeclaration] _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, ^ C:/Users/clang/libunwind/include\unwind.h:277:5: note: previous declaration is here _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, ^ C:...