Bug 4866 – Static-to-dynamic converted manifest constant array gets non-converted type in static/constraint if

If a compile-time constant of type T[N] is converted to a manifest constant of type T[], then the manifest constant gets a wrong type T[N] in static-if or template constraints. In the following code, typeof(dynamic) is correct in static-assert, but wrong in static-if. -------------------- test1.d immutable int[3] statik = [ 1, 2, 3 ]; enum immutable(int)[] dynamic = statik; static assert(is(typeof(dynamic) == immutable(int)[])); static if (! is(typeof(dynamic) == immutable(int)[])) { static assert(0); // (7) } pragma(msg, "!! ", typeof(dynamic)); -------------------- % dmd -c -o- test1.d !! immutable(int[3u]) test1.d(7): Error: static assert (0) is false -------------------- Note the pragma output. Its type is the original static one. The same happens in template constraint: -------------------- test2.d void main() { immutable char[3] statik = "abc"; enum string dynamic = statik; foo(dynamic); // (5) } void foo(T)(T a) if (is(typeof(T) == string)) {} -------------------- % dmd -c -o- test2.d test2.d(5): Error: template test2.foo(T) if (is(typeof(T) == string)) does not match any function template declaration test2.d(5): Error: template test2.foo(T) if (is(typeof(T) == string)) cannot deduce template function from argument types !()(string) -------------------- It's ok if a constant is a scalar: -------------------- test3.d immutable int original = 10; enum real converted = original; static assert(is(typeof(converted) == real)); static if (! is(typeof(converted) == real)) static assert(0); -------------------- % dmd -c -o- test3.d % _ --------------------

Created attachment 763 Patch against dmd r680, fixes VarDeclaration::semantic() The problem was that VarDeclaration::semantic() doesn't take it into account when the variable is a manifest constant or the initializer is non-scalar.

Commit pushed to master at https://github.com/D-Programming-Language/phobos https://github.com/D-Programming-Language/phobos/commit/8c1f68d6e3dca39de6bcef36d5e6bdf7d44ce70c Remove now-unneeded workaround for bug# 4866.