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digitalmars.D.bugs - [Issue 560] New: Cannot escape reference to variadic parameter

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=560

           Summary: Cannot escape reference to variadic parameter
           Product: D
           Version: 0.174
          Platform: PC
               URL: http://www.digitalmars.com/d/function.html
        OS/Version: Windows
            Status: NEW
          Keywords: rejects-valid, spec
          Severity: major
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: deewiant gmail.com
OtherBugsDependingO 511
             nThis:


The following code is directly from the spec:

int test(int i ...)
{
    return i;
}

void main()
{
        test(3);
}

The spec claims that "[a]n implementation may construct the object or array
instance on the stack. Therefore, it is an error to refer to that instance
after the variadic function has returned". This would seem to allow doing this
for parameters which aren't object or array instances. Indeed, the spec gives
the above code as an example of how "[f]or other types, the argument is built
with itself".

I'd say DMD is in error here. I've yet to realise how "int test(int i ...)" is
any better or different from "int test(int i)", though.


--
Nov 18 2006
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=560






Of course I forget to explain the bug itself. Currently, DMD errors out with:

asdf.d(5): Error: escaping reference to variadic parameter i


--
Nov 18 2006
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=560


deewiant gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED





Fixed in DMD 0.176.


--
Dec 03 2006