Bug 12601 – Nested structs get a context pointer even if they don't need one

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]

This is really an issue with the structs implicitly getting a context pointer when they have no reason to own one. I think this bug is filed somewhere already though. As a workaround add 'static' to your C struct definition.

*** This issue has been marked as a duplicate of issue 10276 ***