https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99444
Bug ID: 99444
Summary: [GCOV] Wrong coverage with "case" label in "switch"
statement block
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: gcov-profile
Assignee: unassigned at gcc dot gnu.org
Reporter: njuwy at smail dot nju.edu.cn
CC: marxin at gcc dot gnu.org
Target Milestone: ---
$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/10.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../configure -enable-checking=release -enable-languages=c,c++
-disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 10.2.0 (GCC)
$ cat test.c
int doit(int sel, int n, void *p) {
int *const p0 = p;
switch (sel) {
case 0:
do {
*p0 += *p0;
} while (--n);
return *p0 == 0;
default:
__builtin_abort();
}
}
int main() {
int v0;
v0 = 1;
doit(0, 3, &v0);
__builtin_exit(0);
}
$ gcc -O0 --coverage test.c;./a.out;gcov test;cat test.c.gcov
File 'test.c'
Lines executed:84.62% of 13
Creating 'test.c.gcov'
-: 0:Source:test.c
-: 0:Graph:test.gcno
-: 0:Data:test.gcda
-: 0:Runs:1
1: 1:int doit(int sel, int n, void *p) {
1: 2: int *const p0 = p;
-: 3:
1: 4: switch (sel) {
3: 5: case 0:
-: 6: do {
3: 7: *p0 += *p0;
3: 8: } while (--n);
1: 9: return *p0 == 0;
#####: 10: default:
#####: 11: __builtin_abort();
-: 12: }
-: 13:}
-: 14:
1: 15:int main() {
-: 16: int v0;
1: 17: v0 = 1;
1: 18: doit(0, 3, &v0);
1: 19: __builtin_exit(0);
-: 20:}
-: 21:
Line #5 should only be executed once.
