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POVBA: What is causing this string argument passed to ParamArray to get changed to a number (that looks suspiciously like a pointer)?
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copied!<p>FINAL EDIT: It does indeed appear to be a compiler bug - see the accepted answer.</p> <p>Using VBA within Excel 2007, I have the following code in 'Class1':</p> <pre><code>Option Explicit Public Function strange(dummy As String, ParamArray pa()) Debug.Print pa(LBound(pa)) End Function Public Sub not_strange(dummy As String, ParamArray pa()) Debug.Print pa(LBound(pa)) End Sub Public Function also_not_strange(ParamArray pa()) Debug.Print pa(LBound(pa)) End Function </code></pre> <p>and some mode code in a module:</p> <pre><code>Option Explicit Public Function not_strange_either(dummy As String, ParamArray pa()) Debug.Print pa(LBound(pa)) End Function Public Sub outer(v) Dim c As Class1 Set c = New Class1 Call c.strange("", v(LBound(v))) Call c.not_strange("", v(LBound(v))) Call c.also_not_strange(v(LBound(v))) Call not_strange_either("", v(LBound(v))) End Sub </code></pre> <p>If call 'outer' from the Immediate window like this:</p> <pre><code>call outer(array("a")) </code></pre> <p>I get back output that seems strange:</p> <pre><code> 102085832 a a a </code></pre> <p>It seems to matter whether the called routine is in a class module or not, whether it is a Sub or a Function, and whether or not there is an initial argument. Am I missing something about how VBA is supposed to work? Any ideas?</p> <p>The strange number changes from run to run. I say "looks suspiciously like a pointer" because if I call this:</p> <pre><code>Public Sub outer2(v) Dim c As Class1 Set c = New Class1 Dim ind As Long For ind = LBound(v) To UBound(v) Call c.strange("", v(ind)) Next ind End Sub </code></pre> <p>like so:</p> <pre><code>call outer2(array("a","b","c")) </code></pre> <p>I get back output like:</p> <pre><code> 101788312 101788328 101788344 </code></pre> <p>It's the increment by 16 that makes me suspicious, but I really don't know. Also, passing a value, say by calling:</p> <pre><code>Call c.strange("", CStr(v(ind))) </code></pre> <p>works just fine.</p> <p>EDIT: A little more info...If I assign the return value from 'c.strange' to something instead of throwing it away, I get the same behavior:</p> <pre><code>Public Sub outer3(v) Dim c As Class1 Set c = New Class1 Dim x x = c.strange("", v(LBound(v))) Call c.not_strange("", v(LBound(v))) Call c.also_not_strange(v(LBound(v))) Call not_strange_either("", v(LBound(v))) End Sub </code></pre> <p>Interestingly, if I call my test routines as above, with an argument that results from calling 'Array', the supposed-pointer value changes. However, if I call it like this:</p> <pre><code>call outer([{1,2,3}]) </code></pre> <p>I get back the same number, even if I make the call repeatedly. (The number changes if I switch to another app in Windows, like my browser.) So, now I'm intrigued that the Excel evaluator (invoked with the brackets) seemingly caches its results...</p>

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