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<?php class F {function x(){}} class G extends F {function x():int{ return 42; }} var_dump((new G)->x());;
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
int(42)
preferences:
212.06 ms | 404 KiB | 183 Q