[PATCH] Fix segfault with inlining

[Eric Botcazou]

> I've looked at the C++ testcase
> 
> int foo (int &x)
> {
>   try {
>     return x;
>   }
>   catch (...)
>   {
>     return 0;
>   }
> }
> 
> which exhibits exactly the behavior you quote - return x is considered
> throwing an exception.  The C++ FE doesn't arrange for TREE_THIS_NOTRAP to
> be set here (maybe due to this issue you quote?).

I presume that you compiled with -fnon-call-exceptions?  Otherwise, I don't 
see how something that isn't a call can throw an exception in C++, it should 
be seen at most as possibly trapping, which is less blocking.

> Other than that the patch looks reasonable (I suppose you need
> is_parameter_of only because as we recursively handle the trees
> PARM_DECLs from the destination could already have leaked into
> the tree we recurse into?)

Do you mean that the test on DECL_CONTEXT is superfluous?  Possibly indeed, 
but with nested functions you can have PARM_DECLs of different origins in a 
given function body, although this may be irrelevant for tree-inline.c.

-- 
Eric Botcazou