C++ Compiler Bug with ! bool initialisers ?

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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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