Re: Member initialization of arrays of constants

[<llewelly at dbritsch dot dsl dot xmission dot com>]

[snip]
> 
> If I'm informed correctly, initialization of member constants
> can only be performed via a ctor's initializer-list. Member arrays
> of constants cannot be initialized like aggregates and cannot be
> initialized via a ctor's initializer-list either.

There is nothing in 8.5.1 [dcl.init.aggr] that disallows initializing
  a member array of constant type with a brace-enclosed initializer
  list.

In both of your examples, A is an aggregate, and can therefor be
  initialized with a brace-enclosed initializer list. (See 8.5.1)

The fact that there are const-qualified types in involved does not
  matter in either of your examples; const qualifed types can be
  initialized the same way.

(If const-qualifed members could not be initialized, there would no
  use for them.)

As for static members, see 9.4.2. Static data members are never
  initialized by member-initializer lists. Instead, static data
  members are initialized exactly as you demonstrate in your
  'Example 2' .

(The rule you are probably thinking of is probably based on 12.6.2/4,
  which does not apply to static data members, or to initialization of an 
  aggregate via a brace-enclosed intializer list.)

> 
> Egcs, however, compiles the following code examples fine by
> mistake:
> 
> 
> Example 1:  // ----------------------------------------------------
> 
> struct A
> {
> 	const char a[4];
> 	int i;
> };
> 
> void f()
> {
> 	A a = { {'T','E','S','T'}, 1 };  // not allowed, but compiles
> 	
> 	// This would be okay, if it were an array of non-constants
> 	// in the struct.
> }
> 
> 
> Example 2:  // ----------------------------------------------------
> 
> struct A
> {
> 	const char a[4];
> 	int i;
> };
> 
> class C
> {
> 	static const A a;
> };
> 
> const A C::a = { 'T','E','S','T', 2 };  // not allowed, but compiles
> 

Both of these examples are well-formed, there is not a bug in your
  code, or a bug in gcc.

Thank you for your bug report.