c++/909: Spurious error using nested classes in constructor calls

[rmgiroux@hotmail.com]

>Number:         909
>Category:       c++
>Synopsis:       Spurious error using nested classes in constructor calls
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Nov 27 12:36:00 PST 2000
>Closed-Date:
>Last-Modified:
>Originator:     rmgiroux@hotmail.com
>Release:        gcc version 2.95.2 19991024 (release), gcc version 2.97 20001120 (experimental)
>Organization:
>Environment:
Linux
>Description:
Given a nested class, an attempt to construct an object using a constructor taking a reference of type "const A::Nested &" and another argument fails.  Defaulting the second argument succeeds, letting the Nested object be implicitly constructed succeeds.  Using an old-style cast
for either the argument to the nested type constructor or the nested type constructor also succeed.  WIERD!

A a(A::Nested(i), Z);      // ERROR:  type specifier omitted
			   // for parameter
A b(A::Nested(int(i)), Z); // ERROR:  type specifier omitted
			   // for parameter
A c(A::Nested((int)i), Z); // OK
>How-To-Repeat:
// Just compile this code
class A {
    public:
        struct Nested { Nested(int i) {} };
        
        A(const Nested &n, int *p=0) ;
};

class B {
    public:
        B(const A::Nested &n, int *p=0);
        B(const A &a, int *p=0);
};

int main(void)
{   
    int *Z=0;
    int i=1;
    A a(A::Nested(i), Z);      // ERROR:  type specifier omitted for parameter
    A b(A::Nested(int(i)), Z); // ERROR:  type specifier omitted for parameter
    A c(A::Nested((int)i), Z); // OK
    A d(A::Nested(1), Z);      // OK
    A e(A::Nested(i));         // OK
    A f(i, Z);                 // OK
    
    B g(A::Nested(i), Z);      // ERROR:  type specifier omitted for parameter
    B h(i, Z);                 // OK
}

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: