July 26, 2019
https://issues.dlang.org/show_bug.cgi?id=20086

          Issue ID: 20086
           Summary: -betterC and "Unrestricted use of compile-time
                    features"
           Product: D
           Version: D2
          Hardware: x86
                OS: Windows
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: maxhaton@gmail.com

-------------Example----------------------------------------------------------
auto demo() //otherfile.d
{
    try {
        throw new Exception("I am become death");
    } catch(Exception e)
    {
        return e.msg;
    }
}
extern(C)
void main()
{
   import otherfile : demo;
   auto bad = demo(); //This should not compile
   enum rad = demo(); //This arguably should as per the
                      //(vague) wording of the spec
}

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

The specification implies* that arbitrary CTFE should still be possible, regardless of whether said code actually makes it into the resulting executable.

* The term "Unrestricted* is not defined, which could make this an enhancement rather than a bug. Either way this behaviour should be possible (Across module boundaries, but in the same file raises the question of whether it should compile or not depend on whether the invalid code is actually used)

--