<ais523> ` printf \'#include <stdio.h>\\nint main(void) { float C = 4.0; printf("%%f", C/C++); }\' | gcc -fno-diagnostics-color -Wall -Wextra -x c /dev/stdin

Ā macron is what you put ōver ā long vowel in order to mark it as ā long vowel. Macrons have bēcome mandatory in English on Octōber 14, 2016.