Q147427: DOC: Description of C2354 Error Is Unclear

Article: Q147427
Product(s): Microsoft C Compiler
Version(s): 2.0,2.1,2.2,4.0,4.1,4.2,5.0,6.0
Operating System(s): 
Keyword(s): kbdocerr kbCompiler kbCPPonly kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC420 kbVC500 k
Last Modified: 14-DEC-2001

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The information in this article applies to:

- Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 2.2, 4.0, 4.1 
- Microsoft Visual C++, 32-bit Enterprise Edition, versions 4.2, 5.0, 6.0 
- Microsoft Visual C++, 32-bit Professional Edition, versions 4.2, 5.0, 6.0 
- Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SUMMARY
=======

Neither the error message itself nor the online documentation for the C2354
compiler error clearly specify the cause of this error:

  'reference' : initialization of reference member requires a temporary
  variable

MORE INFORMATION
================

It is illegal to initialize a reference member of a class in the class's
constructor with a temporary variable. An attempt to do so generates the C2354
error, as illustrated by this sample code:

Sample Code
-----------

  int temp() { return 1; }

  class Test
  {
  public:
      int member;
      int& ref_member;
      Test();
  };

  Test::Test() : ref_member( temp() )
  {
  }

When this error is encountered, the solution is to change the code so that the
reference member is not initialized to a temporary variable. The reference must
be initialized to an object that will exist for the lifetime of the reference
member.

Additional query words:

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Keywords          : kbdocerr kbCompiler kbCPPonly kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC420 kbVC500 kbVC600 kbOLDocs 
Technology        : kbVCsearch kbVC400 kbAudDeveloper kbVC220 kbVC410 kbVC420 kbVC500 kbVC600 kbVC200 kbVC210 kbVC32bitSearch kbVC500Search
Version           : :2.0,2.1,2.2,4.0,4.1,4.2,5.0,6.0
Issue type        : kbbug

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