line coverage shows coverage of comments #45102
Description
| Bugzilla Link | 45757 |
| Resolution | FIXED |
| Resolved on | Aug 19, 2020 13:23 |
| Version | trunk |
| OS | Linux |
| CC | @zygoloid,@vedantk,@WesleyRosenblum,@yurybura,@ZequanWu |
Extended Description
For example:
$ cat /tmp/a.c
int f(int x) {
if (x == 42) {
// Comment 1.
return 1;
}
// Comment 2.
return 0;
}
int main() {
f(1);
return 0;
}
$ bin/clang -fcoverage-mapping -fprofile-instr-generate /tmp/a.c
$ ./a.out
$ bin/llvm-profdata merge default.profraw -o default.profdata
$ bin/llvm-cov show a.out -instr-profile=default.profdata
1| 1|int f(int x) {
2| 1| if (x == 42) {
3| 0| // Comment 1.
4| 0| return 1;
5| 0| }
6| 1| // Comment 2.
7| 1| return 0;
8| 1|}
9| |
10| 1|int main() {
11| 1| f(1);
12| 1| return 0;
13| 1|}
Comment 1 gets an execution count of 0 (and shows on red background in the console) but Comment 2 is marked executed.
Does it make sense to have counters for comments, since they can't really be executed?
(This was reported by Chromium's code coverage folks in https://bugs.chromium.org/p/chromium/issues/detail?id=1074518)
It seems gcc/gcov doesn't count the comment lines (gcc -fprofile-arcs -ftest-coverage /tmp/a.c && ./a.out && gcov a.c && cat a.c.gcov).