Re: [C++] Fix decomp ICE with invalid initializer (PR c++/81258)

[Nathan Sidwell <nathan at acm dot org>]

On 06/30/2017 01:24 PM, Jakub Jelinek wrote:

> The initializer for structured binding has to be one of:
> = assignment-expression
> ( assignment-expression )
> { assignment-expression }
> but cp_parser_initializer can parse other forms, with fewer or more
> expressions in there.  Some cases we caught with various cryptic errors
> or pedwarns, but others we just ICEd on.
>
> The following patch attempts to check this.

ok, but ...

> --- gcc/testsuite/g++.dg/cpp1z/decomp21.C.jj	2017-01-19 17:01:21.000000000 +0100
> +++ gcc/testsuite/g++.dg/cpp1z/decomp21.C	2017-06-30 11:07:04.786746784 +0200
> @@ -12,5 +12,5 @@ foo ()
>     auto [ n, o, p ] { a };
>     auto [ q, r, t ] ( s );
>     auto [ u, v, w ] ( s, );      // { dg-error "expected primary-expression before '.' token" }
> -  auto [ x, y, z ] ( a );       // { dg-error "expression list treated as compound expression in initializer" "" { target *-*-* } .-1 }
> +  auto [ x, y, z ] ( a );       // { dg-error "invalid initializer for structured binding" "" { target *-*-* } .-1 }
>   }

The .-1 on the final error is actually about the previous statement, not 
the line it's lexically on.  Could you put it on a line on its own, 
while you're there?

--
Nathan Sidwell