Joseph Ferano
ecf3882fa2
encode-rune! says nothing is written when it answers None, and every None case in the table passed that claim without testing it: an encoder that lays the lead byte down and only then notices the buffer is short returns None exactly as a correct one does. So a known byte goes into scratch, a refused encoding is asked for, and the byte is read back. Storing before the length test turns the line from 65 -1 65 -1 65 into 65 -1 0 -1 0. The read-only claim beside lower-ascii was reasoned from the emitted linkage rather than observed, and observing it was worse than the guess. With (set (at (bytes "Hi") 0) \h): at -O0 the store is emitted against the constant and the program takes SIGSEGV; at -O2 LLVM deletes it as undefined behaviour and the program prints "Hi" and exits 0. The same source either dies or silently does nothing depending on a flag. The comment now says that instead of predicting a segfault.
