How to REALLY strip a binary in MacOs

Question

MacOs 10.6, if I have a file "unwanted.c" which contains:

class secret_thing {
public:
secret_thing() {}
void revealing_method_name() {}
};

main()
{
    secret_thing obj;
    obj.revealing_method_name();
}

Now I do:

$ g++ unwanted.c -o unwanted
$ strip unwanted
$ nm unwanted | grep secret
0000000100000eb8 T __ZN12secret_thing21revealing_method_nameEv 
0000000100000eae T __ZN12secret_thingC1Ev

If I split out the interface and implementation of the secret class, as most people do when writing C++ code, then there are no unwanted symbols in the stripped executable. Sadly, I am handed an existing code base of many thousand lines of code and this isn't one of my choices.

I have tried -fno-rtti, as a wild guess, and that didn't fix anything. I have prayed to the Google gods and found many references to strip clubs, but no helpful links. I have skimmed the man pages for strip, g++, and ld on the mac, and there were no obvious things to try, though the phrase "private externs" was intriguing, I couldn't figure out what to do about that.

[ update ] Sadly, there turns out to be a problem with my attempt to make a small example. Here is a more complicated example, which is closer to what the real problem is, which still has unwanted symbols if it is built optimized.

I apologize for the bad examples. It turns out to be hard to find the smallest actual problem. Many thanks for the answers, though, each answer pushes me close to a solution.

class base {
public:
    virtual int revealing_method_name() = 0;
    virtual ~base() {};
};

class secret_thing : public base {
public:
    int revealing_method_name() { return 0; };
};

class other_thing : public base {
public:
    int revealing_method_name() { return 1; };
};

int main(int argc, char**)
{
    base *object = 0;
    if( argc > 1 ) object = new secret_thing;
    else object = new other_thing;

    return object->revealing_method_name();
}