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digitalmars.D.bugs - [Issue 7766] New: (Full Closures) Chain of nested functions fails

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7766

           Summary: (Full Closures) Chain of nested functions fails
           Product: D
           Version: D2
          Platform: x86_64
        OS/Version: Windows
            Status: NEW
          Severity: minor
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: xinok live.com


--- Comment #0 from Xinok <xinok live.com> 2012-03-24 19:43:02 PDT ---
In the following code, you'd expect it to print 365. However, it prints a
random number instead. The issue is that 'value' is referred to by 'foo', which
is referred to by 'foo2'. DMD fails to detect this chain, so 'value' is
allocated on the stack, not the heap. Once the function 'clbug' returns,
'value' is popped from the stack and so it ends up printing a random number.

value -> foo -> foo2

void main(){
    clbug()();
}

int delegate() clbug(){
    int value = 365;
    int foo(){
        writeln(value);
        return value;
    }
    int foo2(){
        return foo();
    }
    return &foo2;
}

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7766


Don <clugdbug yahoo.com.au> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|NEW                         |RESOLVED
                 CC|                            |clugdbug yahoo.com.au
         Resolution|                            |DUPLICATE


--- Comment #1 from Don <clugdbug yahoo.com.au> 2012-03-27 23:23:02 PDT ---
Duplicate of bug 1841 - it's incorrect closure detection in nested functions.

*** This issue has been marked as a duplicate of issue 1841 ***

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