Author: Peter Senna Tschudin <peter.senna@gmail.com> Returning a negative value for a boolean function seem to have the undesired effect of returning true. Replace -1 by false in a bool-returning function. The diff of the .s file before and after the change (for x86_64): 3907c3907 < movl $1, %ebx --- > xorl %ebx, %ebx while if …