Fix crash when assigning to bindings

Disallow pattern no matching on all control paths Co-authored-by: Jan Lahoda <[email protected]>o
biboudis · Nov 3, 2024 · b08e0df · b08e0df
1 parent b8cbc6f
commit b08e0df
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Showing 8 changed files with 68 additions and 5 deletions.
diff --git a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
@@ -1042,8 +1042,16 @@ public void visitMethodDef(JCMethodDecl tree) {
             }
 
             // Attribute all bindings.
-            for (List<JCVariableDecl> l = tree.bindings; l != null && l.nonEmpty(); l = l.tail) {
-                attribStat(l.head, localEnv);
+            // the bindings have no meaning in the body of the deconstructor,
+            // so enter them in a temporary scope:
+            Env<AttrContext> bindingEnv =
+                    env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup()));
+            try {
+                for (List<JCVariableDecl> l = tree.bindings; l != null && l.nonEmpty(); l = l.tail) {
+                    attribStat(l.head, bindingEnv);
+                }
+            } finally {
+                bindingEnv.info.scope.leave();
             }
 
             chk.checkVarargsMethodDecl(localEnv, tree);
@@ -2434,7 +2442,7 @@ public void visitMatch(JCMatch tree) {
             args = args.tail;
         }
 
-        if (tree.clazz != tree.meth.name) {
+        if (tree.clazz != null && tree.clazz != tree.meth.name) {
             log.error(tree.pos(), Errors.MatchPatternNameWrong);
         }
 

diff --git a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Flow.java b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Flow.java
@@ -617,8 +617,11 @@ public void visitMethodDef(JCMethodDecl tree) {
                 scanStat(tree.body);
                 tree.completesNormally = alive != Liveness.DEAD;
 
-                if (alive == Liveness.ALIVE && !tree.sym.type.getReturnType().hasTag(VOID))
+                if (alive == Liveness.ALIVE && (tree.sym.flags() & PATTERN) != 0) {
+                    log.error(TreeInfo.diagEndPos(tree.body), Errors.MissingMatchStmt);
+                } else if (alive == Liveness.ALIVE && !tree.sym.type.getReturnType().hasTag(VOID)) {
                     log.error(TreeInfo.diagEndPos(tree.body), Errors.MissingRetStmt);
+                }
 
                 clearPendingExits(true);
             } finally {

diff --git a/src/jdk.compiler/share/classes/com/sun/tools/javac/resources/compiler.properties b/src/jdk.compiler/share/classes/com/sun/tools/javac/resources/compiler.properties
@@ -927,6 +927,9 @@ compiler.err.missing.meth.body.or.decl.abstract=\
 compiler.err.missing.ret.stmt=\
     missing return statement
 
+compiler.err.missing.match.stmt=\
+    missing match statement
+
 # 0: type
 compiler.misc.missing.ret.val=\
     missing return value

diff --git a/test/langtools/tools/javac/patterns/declarations/ExampleJSONTest.java b/test/langtools/tools/javac/patterns/declarations/ExampleJSONTest.java
@@ -101,6 +101,8 @@ public pattern Service(String name, int id) {
                     && keys2.get("name") instanceof JSONString(var name2)
                     && keys2.get("id") instanceof JSONNumber(int id2)) {
                 match Service(name2, id2);
+            } else {
+                match Service("error", -1);
             }
         }
     }

diff --git a/test/langtools/tools/javac/patterns/declarations/MatcherFinishingNormally.java b/test/langtools/tools/javac/patterns/declarations/MatcherFinishingNormally.java
@@ -0,0 +1,8 @@
+/**
+ * @test
+ * @enablePreview
+ * @compile/fail/ref=MatcherFinishingNormally.out -XDrawDiagnostics MatcherFinishingNormally.java
+ */
+public class MatcherFinishingNormally {
+    public pattern MatcherFinishingNormally(String content) {}
+}
diff --git a/test/langtools/tools/javac/patterns/declarations/MatcherFinishingNormally.out b/test/langtools/tools/javac/patterns/declarations/MatcherFinishingNormally.out
@@ -0,0 +1,4 @@
+MatcherFinishingNormally.java:7:62: compiler.err.missing.match.stmt
+- compiler.note.preview.filename: MatcherFinishingNormally.java, DEFAULT
+- compiler.note.preview.recompile
+1 error
diff --git a/test/langtools/tools/javac/patterns/declarations/PatternDeclarationErrors.java b/test/langtools/tools/javac/patterns/declarations/PatternDeclarationErrors.java
@@ -67,4 +67,37 @@ public class R2 {
         pattern R2(int i) { match R2(42); }
         pattern R2(int i) { match R2(42); }
     }
+
+
+    public class Point {
+        final int x;
+        final int y;
+
+        protected Point(int x, int y) {
+            this.x = x;
+            this.y = y;
+        }
+
+        protected pattern Point(int x, int y) {
+            match Point(this.x, this.y);
+        }
+    }
+
+    public class GreatPoint extends Point {
+        final int magnitude;
+
+        public GreatPoint(int x, int y, int magnitude) {
+            super(x, y);
+            if (magnitude < 0) throw new IllegalArgumentException();
+            this.magnitude = magnitude;
+        }
+
+        public pattern GreatPoint(int x, int y, int magnitude) {
+            if (this instanceof Point(var X, var Y)) {
+                x = X;
+                y = Y;
+            }
+            match GreatPoint(x, y, this.magnitude);
+        }
+    }
 }
diff --git a/test/langtools/tools/javac/patterns/declarations/PatternDeclarationErrors.out b/test/langtools/tools/javac/patterns/declarations/PatternDeclarationErrors.out
@@ -11,7 +11,9 @@ PatternDeclarationErrors.java:49:13: compiler.err.pattern.declaration.no.throws
 PatternDeclarationErrors.java:52:24: compiler.err.pattern.declaration.cant.throw.exception
 PatternDeclarationErrors.java:53:13: compiler.err.pattern.declaration.no.throws
 PatternDeclarationErrors.java:58:24: compiler.err.invalid.canonical.deconstructor.in.record: R
+PatternDeclarationErrors.java:97:17: compiler.err.cant.assign.val.to.var: final, x
+PatternDeclarationErrors.java:98:17: compiler.err.cant.assign.val.to.var: final, y
 PatternDeclarationErrors.java:29:13: compiler.err.unreachable.stmt
 - compiler.note.preview.filename: PatternDeclarationErrors.java, DEFAULT
 - compiler.note.preview.recompile
-14 errors
+16 errors