https://issues.dlang.org/show_bug.cgi?id=12834

          Issue ID: 12834
           Summary: implicite destructor cannot call invariant
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: normal
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: r.sagitario@gmx.de

Compile this code with "dmd test.d":

struct Treap(E)
{
    ~this()
    {
    }
}

class P
{
    invariant()
    {
    }

    Treap!int ranges;
}

It yields:

Error: pure function 'test.P.~this' cannot call impure function
'test.P.__invariant'
test.d(9): Error: safe function 'test.P.~this' cannot call system function
'test.P.__invariant'
test.d(9): Error: @nogc function 'test.P.~this' cannot call non-@nogc function
'test.P.__invariant'

It seems the attributes are inferred without the invariant. Annotatibg the invariant with "@nogc pure nothrow const" can work, but get's viral if you call other functions.

This came up when trying to enable debug(INVARIANT) in gc.d. I failed to add appropriate annotation there, because you cannot overload on @nogc.

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