6326693: variable x might already have been assigned, when assignment is in catch block

Reviewed-by: mcimadamore

src/share/classes/com/sun/tools/javac/comp/Flow.java

@@ -1945,10 +1945,17 @@ public class Flow {
                 }
             }
 
+            /*  The analysis of each catch should be independent.
+             *  Each one should have the same initial values of inits and
+             *  uninits.
+             */
+            final Bits initsCatchPrev = new Bits(initsTry);
+            final Bits uninitsCatchPrev = new Bits(uninitsTry);
+
             for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
                 JCVariableDecl param = l.head.param;
-                inits.assign(initsTry);
-                uninits.assign(uninitsTry);
+                inits.assign(initsCatchPrev);
+                uninits.assign(uninitsCatchPrev);
                 scan(param);
                 inits.incl(param.sym.adr);
                 uninits.excl(param.sym.adr);

test/tools/javac/T6326693/FinalVariableAssignedToInCatchBlockTest.java

+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 6356530
+ * @summary -Xlint:serial does not flag abstract classes with concrete methods/members
+ * @compile/fail/ref=FinalVariableAssignedToInCatchBlockTest.out -XDrawDiagnostics FinalVariableAssignedToInCatchBlockTest.java
+ */
+
+import java.io.IOException;
+
+public class FinalVariableAssignedToInCatchBlockTest {
+    public void m1(int o)
+    {
+        final int i;
+        try {
+            if (o == 1) {
+                throw new IOException();
+            } else if (o == 2) {
+                throw new InterruptedException();
+            } else {
+                throw new Exception();
+            }
+        } catch (IOException e) {
+            i = 1;
+        } catch (InterruptedException ie) {
+            i = 2;
+        } catch (Exception e) {
+            i = 3;
+        } finally {
+            i = 4;
+        }
+    }
+
+    public void m2(int o)
+    {
+        final int i;
+        try {
+            if (o == 1) {
+                throw new IOException();
+            } else if (o == 2) {
+                throw new InterruptedException();
+            } else {
+                throw new Exception();
+            }
+        } catch (IOException e) {
+            i = 1;
+        } catch (InterruptedException ie) {
+            i = 2;
+        } catch (Exception e) {
+            i = 3;
+        }
+    }
+
+    public void m3(int o) throws Exception
+    {
+        final int i;
+        try {
+            if (o == 1) {
+                throw new IOException();
+            } else if (o == 2) {
+                throw new InterruptedException();
+            } else {
+                throw new Exception();
+            }
+        } catch (IOException e) {
+            i = 1;
+        } catch (InterruptedException ie) {
+            i = 2;
+        }
+        i = 3;
+    }
+}

test/tools/javac/T6326693/FinalVariableAssignedToInCatchBlockTest.out

+FinalVariableAssignedToInCatchBlockTest.java:52:13: compiler.err.var.might.already.be.assigned: i
+FinalVariableAssignedToInCatchBlockTest.java:92:9: compiler.err.var.might.already.be.assigned: i
+2 errors