variable x cannot be read at compile time (ctfe)

[bearophile]

> I think it's a problem of nested delegates at CT. But if this 
> is the problem, dmd used to give a more clear error message.

Two minimized programs that show the problems:

-------------

import std.algorithm: filter;
import std.array: array;
auto foo(in int x) {
     return [1, 2].filter!(i => x)();
}
enum a = foo(3).array();
void main() {}



temp.d(4): Error: variable x cannot be read at compile time

-------------

import std.array: array;
enum a = [1, 2].array();
void main() {}



...\src\druntime\import\core\memory.d(251): Error:
gc_malloc cannot be interpreted at compile time, because it has 
no available source code

-------------

Bye,
bearophile