static const char xdigits[16] = {

"0123456789ABCDEF"

};

Note that while this xdigits array has a length of 16, the string it is being initialized to has a length of 17, due to the implicit null terminator. Thus, an additional '\0' will be written just past the end of this global. I believe this could cause unpredictable effects depending upon how the compiler and linker handle this situation.

The fix is simple, just write out a list of comma separated characters to eliminate the null terminator or make xdigits have a length of 17.

Thanks,
Mark Winterrowd