Re: compiler bug -- mistaken C3821 when invoking new in ctor-initializer-list (regression)

From:
"Ben Voigt [C++ MVP]" <bvoigt@newsgroup.nospam>
Newsgroups:
microsoft.public.dotnet.languages.vc
Date:
Thu, 9 Jul 2009 09:11:18 -0500
Message-ID:
<OGGZh8JAKHA.4984@TK2MSFTNGP05.phx.gbl>
Jeroen Mostert wrote:

Ben Voigt [C++ MVP] wrote:

Please validate this bug:
https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=473352

Here is the test case:

#pragma managed(push, off)
#include <list>

class C3821
{
     std::list<int*>* p;

public:
     C3821( size_t n )
            : p(new std::list<int*>[n])
     {
     }
};
#pragma managed(pop)

I've been able to verify that it works in VS2005 SP1 but not in
VS2008 SP1, appreciate anyone who can check it on RTM versions or
has VS2010 beta handy.

VS 2010 output:

1>ClCompile:
1> c3821.cpp
1>c3821.cpp(9): error C2711: 'C3821::C3821' : this functon cannot be
compiled as managed, consider using #pragma unmanaged
1> #pragma unmanaged is in effect
1> c3821.cpp(11) : see source of the previous compiler
diagnostic 1>c3821.cpp(12): error C3821: 'C3821::C3821(size_t)':
managed type or function cannot be used in an unmanaged function

So you have to use #pragma unmanaged, which also happens to be in
effect, so the error is obvious, right? (And yes, this is verbatim
output, it's "functon" -- well, it's a beta.)


Beta status is no excuse when that identical error message and (mis)spelling
is produced by the VS2008 SP1 compiler ;)

C2711 is confusing because unmanaged mode is selected. But I think it is
produced as a side effect of the C3821. It's trying to recover from C3821
by compiling the code to MSIL instead of native, and my pragma forbids that,
hence the C2711.

The issue is C3821. There is no use of any managed type, and the error
message makes no attempt to explain which type or function the compiler
thought was being used.

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