ADDITIONAL SYSTEM INFORMATION :
os: generic
java: 17, 20, 21

A DESCRIPTION OF THE PROBLEM :
Description
pleease see the followed code:

public class Case {
static void run(Object obj) {
if (obj instanceof Integer a || obj instanceof String b || obj instanceof String[] c) {
System.out.print(c);
}
}
}

the compileer show error at the line 4: c cannot be resolved to a variable

Based on the principle of doing better： Since it supports the use of the line 3，so I recommand that add support for the used variable defined in the instanceof statements. or show compiler error at the line 3

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
no errors or show compiler error at the line 3
ACTUAL -
compiler error : c cannot be resolved to a variable

FREQUENCY : always