C++ tips: Disable "Enable Incremental Linking" linker option to get better symbols

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By default, Visual Studio does not generate very friendly symbol names. For example, if you build below code, then run it under windbg:

#include "stdafx.h"

class MyClass
{
public:
 MyClass();
 void Func1();
};

MyClass::MyClass()
{
 printf("in MyClass::MyClass\r\n");
}

void MyClass::Func1()
{
 printf("in MyClass::Func1\r\n");
}

int _tmain(int argc, _TCHAR* argv[])
{
 MyClass obj1;
 obj1.Func1();
 return 0;
}

If you check the assembly of wmain, you will see some unfriendly symbol names as highlighted below:

0:000> uf testsymbol!wmain
......

   25 012e720e 8d4dfb          lea     ecx,[ebp-5]
   25 012e7211 e8fbe0ffff      call    testSymbol!ILT+780(??0MyClassQAEXZ) (012e5311)   >>>>this is the constructor call
   26 012e7216 8d4dfb          lea     ecx,[ebp-5]
   26 012e7219 e801e7ffff      call    testSymbol!ILT+2330(?Func1MyClassQAEXXZ) (012e591f) >>>>this is obj1.Func1();
......

If you check the assembly in VS directly, VS shows you the friendly name since it has the right info to figure out the symbol names for you:

 MyClass obj1;
013C720E  lea         ecx,[obj1] 
013C7211  call        MyClass::MyClass (13C5311h) 
 obj1.Func1();
013C7216  lea         ecx,[obj1] 
013C7219  call        MyClass::Func1 (13C591Fh) 

My coworker tells my set the "Enable Incremental Linking" linker option to no can avoid this issue:

I set this option to no, then rebuild the code, this time, I get friendly names in windbg now:

0:000> uf testsymbol!wmain
......

   25 010810be 8d4dfb          lea     ecx,[ebp-5]
   25 010810c1 e83affffff      call    testSymbol!MyClass::MyClass (01081000)
   26 010810c6 8d4dfb          lea     ecx,[ebp-5]
   26 010810c9 e882ffffff      call    testSymbol!MyClass::Func1 (01081050)
   27 010810ce 33c0            xor     eax,eax
......