#include <stdio.h>
 
    // defeat inline optimizations of 'a / b * b' to 'a'
    extern double bodge(int base, int divisor) {
        return static_cast<double>(base) / static_cast<double>(divisor);
    }
 
    int main() {
        int errors = 0;
        for (int b = 1; b < 100; ++b) {
            for (int d = 1; d < 100; ++d) {
                // b / d * d ... should == b
                double res = bodge(b, d) * static_cast<double>(d);
                // but it doesn't always
                if (res != static_cast<double>(b))
                    ++errors;
            }
        }
        printf("errors: %d\n", errors);
    }
 

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