[C++ Patch/RFC] PR 57092

[Jason Merrill]

On 04/29/2013 05:05 AM, Paolo Carlini wrote:
> in this 4.8/4.9 Regression, finish_decltype_type doesn't handle
> ADDR_EXPR.

Hmm...we're seeing the regression because previously 
finish_decltype_type would have just returned the type of the template 
parameter so it wouldn't ever see the ADDR_EXPR at instantiation time. 
But we want to form a DECLTYPE_TYPE so that the mangling is correct. 
Perhaps the right solution is to handle this case specially in 
tsubst/DECLTYPE_TYPE: If id is true and the original expr is a 
TEMPLATE_PARM_INDEX, just instantiate the type of the template parm 
rather than its value.

Jason