From af5a14ac6d1512d8174de907019d58f99c00a536 Mon Sep 17 00:00:00 2001
From: Sergey Prigogin <eclipse.sprigogin@gmail.com>
Date: Wed, 28 Aug 2013 13:51:59 -0700
Subject: [PATCH] Bug 390782 - NPE in
 AssignmentToItselfChecker$1.isAssignmentToItself

---
 .../checkers/AssignmentToItselfChecker.java   | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/codan/org.eclipse.cdt.codan.checkers/src/org/eclipse/cdt/codan/internal/checkers/AssignmentToItselfChecker.java b/codan/org.eclipse.cdt.codan.checkers/src/org/eclipse/cdt/codan/internal/checkers/AssignmentToItselfChecker.java
index f216659e03f..cbf50c72ac0 100644
--- a/codan/org.eclipse.cdt.codan.checkers/src/org/eclipse/cdt/codan/internal/checkers/AssignmentToItselfChecker.java
+++ b/codan/org.eclipse.cdt.codan.checkers/src/org/eclipse/cdt/codan/internal/checkers/AssignmentToItselfChecker.java
@@ -41,16 +41,20 @@ public class AssignmentToItselfChecker extends AbstractIndexAstChecker {
 				return PROCESS_CONTINUE;
 			}
 
-			private boolean isAssignmentToItself(IASTExpression e) {
-				if (e instanceof IASTBinaryExpression) {
-					IASTBinaryExpression binExpr = (IASTBinaryExpression) e;
+			private boolean isAssignmentToItself(IASTExpression expr) {
+				if (expr instanceof IASTBinaryExpression) {
+					IASTBinaryExpression binExpr = (IASTBinaryExpression) expr;
 					if (binExpr.getOperator() == IASTBinaryExpression.op_assign) {
-						String op1 = binExpr.getOperand1().getRawSignature();
-						String op2 = binExpr.getOperand2().getRawSignature();
-						String expr = binExpr.getRawSignature();
-						return op1.equals(op2)
-								// When macro is used, RawSignature returns macro name, see bug 321933
-								&& !op1.equals(expr);
+						IASTExpression operand1 = binExpr.getOperand1();
+						IASTExpression operand2 = binExpr.getOperand2();
+						if (operand1 != null && operand2 != null) {
+							String op1 = operand1.getRawSignature();
+							String op2 = operand2.getRawSignature();
+							String exprImage = binExpr.getRawSignature();
+							return op1.equals(op2)
+									// When macro is used, RawSignature returns macro name, see bug 321933
+									&& !op1.equals(exprImage);
+						}
 					}
 				}
 				return false;