[Bug c++/42603] New: decltype not supported for parent class specifier

[gccbugs at blaggart dot com]

file: test.cpp

template <class T>
T make();

struct p {};
struct c : decltype(make<p>()) {};

compilation command:
g++ -c -std=c++0x test.cpp

output:
test.cpp:5: error: expected class-name before 'decltype'
test.cpp:5: error: expected '{' before 'decltype'
test.cpp:5: error: expected unqualified-id before '{' token

Expected result:

c should inherit p and everything should compile fine.

Note that this can be worked around with the following modification:

template <class T>
T make();

template <class T> struct wrap {
    typedef T type;
};

struct p {};
struct c : wrap< decltype(make<p>()) >::type {};

However this modification is cumbersome and seems pointless.


-- 
           Summary: decltype not supported for parent class specifier
           Product: gcc
           Version: 4.4.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gccbugs at blaggart dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42603