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Compiler Warning (level 1) C4005

Error Message

'identifier' : macro redefinition

The macro identifier is defined twice. The compiler uses the second macro definition.

To fix by checking the following possible causes

  1. Defining a macro on the command line and in the code with a #define directive.

  2. Macros imported from include files.

To fix by using the following possible solutions

  1. Remove one of the definitions.

  2. Use an #undef directive before the second definition.

The following sample generates C4005:

// C4005.cpp
// compile with: /W1 /EHsc
#include <iostream>
using namespace std;

#define TEST "test1"
#define TEST "test2"   // C4005 delete or rename to resolve the warning

int main() {
   cout << TEST << endl;