Bug 6696 – Error messages for const/immutable arrays given to immutable/const

A wrong D2 program: void foo(immutable ref int[5] a) {} void bar(const ref int[5] a) {} void main() { const int[5] arr1; foo(arr1); // line 5 immutable int[5] arr2; bar(arr2); // line 7 } DMD 2.055 prints: test.d(5): Error: function test.foo (ref immutable immutable(int[5u]) a) is not callable using argument types (const(int[5u])) test.d(5): Error: cast(immutable(int[5u]))arr1 is not an lvalue test.d(7): Error: cast(const(int[5u]))arr2 is not an lvalue The first error message is almost good, but why does it print "immutable immutable"? I think the second error message is useless. In line 7 the bar(arr2) call gives just a "arr2 is not an lvalue" that I think is not good enough. So for this program I think a better error message printout is something like: test.d(5): Error: function test.foo(ref immutable(int[5]) a) is not callable using argument types (const(int[5])). test.d(7): Error: function test.foo(ref const(int[5]) a) is not callable using argument types (immutable(int[5])).

Only error now is: Error: function test.foo (ref immutable(int[5u]) a) is not callable using argument types (const(int[5u])) line 7 is now allowed apparently.