alloca and parameter passing

[Jeff Law]

On 12/29/2015 11:06 AM, Florian Weimer wrote:
> About fifteen years ago, GCC apparently did not seem to support calling
> alloca as a nested expression in a function argument.  I can't image how
> this limitation survived the switch to treessa.  Is it true that it's
> long gone now?
I don't explicitly recall it going away.

Note that the move to tree-ssa actually makes this kind of thing easier 
as the gimplifier will do the evaluation of the argument into a 
temporary and use the temporary in the function call.

Jeff