https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120332
--- Comment #1 from Wentao Zhang <wentaoz5 at illinois dot edu> --- Another example affected by "no code", adapted from https://sources.debian.org/src/procps/2%3A4.0.2-3/src/ps/display.c/#L636 "No code" version: 1: 2:int main(void) { 1: 3: int i = 11; 1: 4: while (i--) { 11: 5: switch(i) { branch 0 taken 4 (fallthrough) branch 1 taken 7 4: 6: default: 4: 7: g++; 12: 8: case 1: branch 0 taken 11 branch 1 taken 1 (fallthrough) condition outcomes covered 2/2 -: 9: case 2: -: 10: case 3: -: 11: case 4: -: 12: case 5: -: 13: case 6: -: 14: case 7: -: 15: (void *) 0; -: 16: // g++; -: 17: } -: 18: } -: 19:} Normal version by uncommenting the 2nd "g++" statement: 1: 2:int main(void) { 1: 3: int i = 11; 12: 4: while (i--) { branch 0 taken 11 branch 1 taken 1 (fallthrough) condition outcomes covered 2/2 11: 5: switch(i) { branch 0 taken 4 (fallthrough) branch 1 taken 7 4: 6: default: 4: 7: g++; 11: 8: case 1: -: 9: case 2: -: 10: case 3: -: 11: case 4: -: 12: case 5: -: 13: case 6: -: 14: case 7: -: 15: (void *) 0; 11: 16: g++; -: 17: } -: 18: } -: 19:} In the first version of "no code", line coverage, branch coverage and MC/DC at line 8 for "case 1" label seem to all refer to loop predicate "i--".
