September 04, 2020
https://issues.dlang.org/show_bug.cgi?id=21223

          Issue ID: 21223
           Summary: nothrow constructor may call throwing constructor with
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: moonlightsentinel@disroot.org

Consider the following example:

==============================================================
struct HasDtor
{
    ~this()
    {
        // Enforce @system, ... just to be sure
        __gshared int i;
        if (++i)
            throw new Exception(new immutable(char)[](10));
    }
}

// The user-defined dtor matches the ctor attributes
struct Strict
{
    HasDtor member;

    this(int) pure nothrow @nogc @safe {}

    ~this() pure nothrow @nogc @safe {}
}

==============================================================

Compiling this code with `-preview=dtorfields` will insert a potential call to HasDtor.~this into Strict.this. This is obviously an error because the destructor doesn't match the attributes enforced by the constructor, yet only pure nothrow @nogc will be reported while non-nothrow is accepted.

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