https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77299
--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This has regression repeatedly.
GCC 5 warned about all the unused statements:
unused.C: In function 'int main()':
unused.C:5:12: warning: statement has no effect [-Wunused-value]
INT64_MIN; // no warning
^
unused.C:6:12: warning: statement has no effect [-Wunused-value]
INT64_MIN; // no warning
^
unused.C:7:12: warning: statement has no effect [-Wunused-value]
INT64_MAX; // -Wunused-value
^
unused.C:8:12: warning: statement has no effect [-Wunused-value]
INT64_MAX; // -Wunused-value
^
unused.C:9:4: warning: statement has no effect [-Wunused-value]
1; // -Wunused-value
^
unused.C:10:4: warning: statement has no effect [-Wunused-value]
0; // -Wunused-value
^
unused.C:11:16: warning: statement has no effect [-Wunused-value]
INT64_MIN + 0; // -Wunused-value
^
GCC 6 lost the first two warnings:
unused.C: In function 'int main()':
unused.C:7:12: warning: statement has no effect [-Wunused-value]
INT64_MAX; // -Wunused-value
^
unused.C:8:12: warning: statement has no effect [-Wunused-value]
INT64_MAX; // -Wunused-value
^
unused.C:9:4: warning: statement has no effect [-Wunused-value]
1; // -Wunused-value
^
unused.C:10:4: warning: statement has no effect [-Wunused-value]
0; // -Wunused-value
^
unused.C:11:13: warning: statement has no effect [-Wunused-value]
INT64_MIN + 0; // -Wunused-value
^
Then GCC 9 lost the next two:
unused.C: In function 'int main()':
unused.C:9:3: warning: statement has no effect [-Wunused-value]
9 | 1; // -Wunused-value
| ^
unused.C:10:3: warning: statement has no effect [-Wunused-value]
10 | 0; // -Wunused-value
| ^
unused.C:11:13: warning: statement has no effect [-Wunused-value]
11 | INT64_MIN + 0; // -Wunused-value
| ^
