C++ Compiler Bug with ! bool initialisers ?

[NewsBot]

I think I've discovered a compiler bug.

 

Well, I don't know wether this is known or not, but if I could get confirmations with both the VS2005 and VS2008 c++ compilers.

 

I'm working my way through [the safe bool idiom article], and specifically, i found the error implementing the OperatorNot class:

 

// operator! version

class Testable {

bool not_ok_;

public:

explicit Testable(bool b=true):not_ok_(!b) {}

 

bool operator!() const {

return not_ok_;

}

};

 

Notice the not (!) in the initialiser.

 

When run it does not initialise the not_ok member to false, when instanitating the class like:

Testable test;

Here's the disassembly of the constructor:

public:

explicit Testable(bool b=true):ok_(b) {}

004115F0 push ebp

004115F1 mov ebp,esp

004115F3 sub esp,0CCh

004115F9 push ebx

004115FA push esi

004115FB push edi

004115FC push ecx

004115FD lea edi,[ebp-0CCh]

00411603 mov ecx,33h

00411608 mov eax,0CCCCCCCCh

0041160D rep stos dword ptr es:[edi]

0041160F pop ecx

00411610 mov dword ptr [ebp-8],ecx

00411613 mov eax,dword ptr [this]

00411616 mov cl,byte ptr

00411619 mov byte ptr [eax],cl

0041161B mov eax,dword ptr [this]

0041161E pop edi

0041161F pop esi

00411620 pop ebx

00411621 mov esp,ebp

00411623 pop ebp

00411624 ret 4

WTF.

I've checked multiple times, and the original source does have the !.

Yet when I switch to the disassembly view, and single-step into the constructor, it shows it (the bit marked in red) without the !. The bit embolded is the actual native code setting the member.

Am I missing something ?

 

This is using VS2005sp1 (c1xx.dll version 14.0.50727.762)

 

 

 

 

 

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