[LLVMdev] landingpad instruction documentation is vague

[Bill Wendling]

On Jan 11, 2012, at 3:15 AM, 陳韋任 wrote:

> On Wed, Jan 11, 2012 at 11:37:50AM +0100, Duncan Sands wrote:
>> Hi Yuri,
>> 
>>> I am new to the landingpad (which is relatively new too).
>>> Documentation http://llvm.org/docs/LangRef.html#i_landingpad leaves some
>>> questions open:
>>> 
>>> 1. What happens when actual exception type isn't listed in catch or
>>> filter clauses? Does it still return the corresponding structure like if
>>> it was listed? Or behavior is undefined?
>> 
>> if it doesn't match a clause then the exception continues to be unwound.
>> Note that you can match a catch clause without being equal to the type
>> in the catch clause (for example because the catch clause type represents
>> some class B, and thus will also match a class A if B derives from A).
> 
> [snippet]
> 
>  It would be great if this can be put somewhere on the website to clear
> LLVM exception handling further. ;)
> 
Hi 陳韋任,

This isn't an llvm-specific feature, but how exceptions work in general.

-bw