delegates and temporary struct

Jack Applegame japplegame at gmail.com
Thu May 16 15:53:55 PDT 2013


Look at this code:
>import std.stdio;
>
>class Foo {
>  int value = 123456;
>}
>
>struct Bar {
>  this(Foo f) { foo = f; }
>  @property auto lambda() {
>    return (){ writefln("value = %s", foo.value); };
>  }
>  Foo foo;
>}
>auto getLambda(Foo f) {
>  return Bar(f).lambda; // lambda closure points to temporary 
> Bar on the stack
>}
>void main() {
>  Foo foo = new Foo;
>  auto lambda = getLambda(foo);
>  lambda(); // undefined behaviour? prints some number, but not 
> 123456
>}
It compiles, but result is unpredictable.

Platform: Windows 7, dmd 2.062

For reproducing this behaviour it's necessary to omit -inline and 
-O flags, try simple "rdmd test.d"


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