[Issue 12601] New: Nested functions and properties increase size of struct.

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=12601

          Issue ID: 12601
           Summary: Nested functions and properties increase size of
                    struct.
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: major
          Priority: P1
         Component: DMD
          Assignee: nob...@puremagic.com
          Reporter: mrdark...@gmail.com

Hi, all.

I found next unexpected behaviour: Nested functions and properties increase
size of struct.

[CODE]
import std.stdio;

int main()
{
        struct A
        {
                ushort variable;
        }

        struct B
        {
                ushort variable;
        }

        struct C
        {
                ushort variable;
                @property int var()
                {
                        return variable;
                }
        }

        A a;
        B b;
        C c;

        @property var(B v)
        {
                return v.variable;
        }

        writeln("A.sizeof: ", a.sizeof);
        writeln("B.sizeof: ", b.sizeof);
        writeln("C.sizeof: ", c.sizeof);
        return 0;
}

[/CODE]

[OUTPUT]
A.sizeof: 2
B.sizeof: 2 /// property for this struct does not change size
C.sizeof: 16 /// <- real size should be 2 (has nested function-property)
[/OUTPUT]

Reproduced on:
- DMD 2.065
- GDC 4.8.2

This behaviour is founded when used next code:
[CODE]
    struct FrameHeader
    {
        mixin(
            bitfields!(
                bool, "fin", 1,
                bool, "rsv1", 1,
                bool, "rsv2", 1,
                bool, "rsv3", 1,
                FrameOpcode, "opcode", 4,
                bool, "mask", 1,
                ubyte, "payloadLength", 7
            )
        );
    }

    long receive(void[] value)
    {
        /// reading is here
    }

    long receive(T)(ref T value) if (is(T == struct))
    {
        return receive((cast(void*)&value)[0..value.sizeof]); /// try read 16
bytes instead of 2.
    }

    // ...

FrameHeader frameHeader;
receive(frameHeader);
[/CODE]

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