Merge pull request #2305 from aschackmull/java/overflowcheck-conditionalexpr

Java: Add ConditionalExpr to overflow candidate pattern.

java/ql/src/Likely Bugs/Comparison/UselessComparisonTest.ql

@@ -132,6 +132,11 @@ Expr overFlowCand() {
   result.(AssignExpr).getRhs() = overFlowCand()
   or
   result.(LocalVariableDeclExpr).getInit() = overFlowCand()
+  or
+  exists(ConditionalExpr c | c = result |
+    c.getTrueExpr() = overFlowCand() and
+    c.getFalseExpr() = overFlowCand()
+  )
 }
 
 predicate positiveOrNegative(Expr e) { positive(e) or negative(e) }

java/ql/test/query-tests/UselessComparisonTest/A.java

@@ -121,6 +121,11 @@ public class A {
     }
   }
 
+  void overflowTests2(int[] a, boolean b) {
+    int newlen = b ? (a.length + 1) << 1 : (a.length >> 1) + a.length;
+    if (newlen < 0) overflow();
+  }
+
   static final long VAL = 100L;
 
   long overflowAwareIncrease(long x) {