Compiler Warning (level 1) C4786 (Windows CE 5.0)

Windows CE 5.0
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'identifier' : identifier was truncated to 'number' characters in the debug information

The identifier string exceeded the maximum allowable length and was truncated.

The debugger cannot debug code with symbols longer than 255 characters. In the debugger, you cannot view, evaluate, update, or watch the truncated symbols.

This limitation can be overcome by shortening identifier names. The example code below demonstrates this method.

A trace mechanism can also be used to solve this problem. A trace mechanism is like the printf statements in the code. It keeps track of what is going on in an application during the debugging process.

The _ASSERT, _ASSERTE, _RPTn and _RPTFn macros provide concise and flexible ways to perform the trace. These macros are not defined when _DEBUG is not defined.

The example below demonstrates a situation that would cause this compiler warning to occur, and the solution to this problem.

 //sample1.cpp
 //In this program we have a class of a very long name.
 //We instantiate an object of that class type. We will
 //get multiple C4786 warnings. The comments below
 //demonstrate the solution to this problem.

 #define a_really_long_class_name 
a_really_really_really_really_really_really_really_really_really_really_
really_really_really_really_really_really_really_really_really_really_
really_really_really_really_really_really_really_really_really_really_
really_really_really_really//_really_long_class_name

 //SOLUTION: Uncomment the lines below

 //#ifdef _DEBUG
 //#define a_really_long_class_name A_SHORT_CLASS_NAME
 //#endif

 class a_really_long_class_name
 {
 public:
a_really_long_class_name() {};
int m_data;
 };

 void main()
 {
 a_really_long_class_name test_obj;
 test_obj.m_data = 12;
 }

The following example demonstrates that templates with some long class names as their parameters can easily exceed the 255 character limit. Solutions to the problem are also provided.

 //sample2.cpp
 //SOLUTION1: uncomment the next 4 lines
 //#ifdef _DEBUG
 //#define VeryLongClassNameA A
 //#define VeryLongClassNameB B
 //#endif

 //SOLUTION2: An alternative solution:
 //uncomment the next 3 lines.
 //#ifdef _DEBUG
 //#define SomeRandomClass SRC
 //#endif

 template <class A1, class A2, class A3, class A4>
 class VeryLongClassNameA{};

 template <class B1, class B2, class B3>
 class VeryLongClassNameB{};

 template <class C1, class C2>
 class VeryLongClassNameC{};

 template <class D1>
 class VeryLongClassNameD{};

 class SomeRandomClass{};

 typedef VeryLongClassNameD<SomeRandomClass> ClassD ;
 typedef VeryLongClassNameC<SomeRandomClass, ClassD> ClassC;
 typedef VeryLongClassNameB<SomeRandomClass, ClassC, ClassD> ClassB;
 typedef VeryLongClassNameA<SomeRandomClass, ClassB, ClassC, ClassD> ClassA;

 void SomeRandomFunction(ClassA aobj){}

 void main()
 {
ClassA AObj ;
SomeRandomFunction(AObj) ;
 }

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