Rule 7.0.6: Ignore compound expressions

Author: lcartey

cpp/misra/src/rules/RULE-7-0-6/NumericAssignmentTypeMismatch.ql

@@ -69,8 +69,8 @@ class NumericType extends Type {
 }
 
 predicate isAssignment(Expr source, NumericType targetType, string context) {
-  // Assignment operator
-  exists(Assignment assign |
+  // Assignment operator (but not compound assignment)
+  exists(AssignExpr assign |
     assign.getRValue() = source and
     context = "assignment"
   |
@@ -191,7 +191,7 @@ predicate hasConstructorException(FunctionCall call) {
  */
 class IdExpression extends VariableAccess {
   IdExpression() {
-    // Not a member variable
+    // Not a member variable access (no dot or arrow)
     (
       not exists(this.getQualifier())
       or

cpp/misra/test/rules/RULE-7-0-6/test.cpp

@@ -359,4 +359,25 @@ void test_references() {
   std::uint64_t l4 = 1000;
   std::uint64_t &l5 = l4;
   f14(l5); // NON_COMPLIANT - narrowing conversion through reference
+}
+
+// Test compound assignments - rule does not apply to compound assignments
+void test_compound_assignments() {
+  std::uint8_t l1 = 10;
+  std::uint16_t l2 = 100;
+  std::int8_t l3 = 5;
+  float l4 = 1.5f;
+
+  l1 += l2;  // COMPLIANT - compound assignment, rule does not apply
+  l1 -= l3;  // COMPLIANT - compound assignment, rule does not apply
+  l2 *= l1;  // COMPLIANT - compound assignment, rule does not apply
+  l2 /= l3;  // COMPLIANT - compound assignment, rule does not apply
+  l1 %= l3;  // COMPLIANT - compound assignment, rule does not apply
+  l2 &= l1;  // COMPLIANT - compound assignment, rule does not apply
+  l2 |= l3;  // COMPLIANT - compound assignment, rule does not apply
+  l2 ^= l1;  // COMPLIANT - compound assignment, rule does not apply
+  l2 <<= 2;  // COMPLIANT - compound assignment, rule does not apply
+  l2 >>= 1;  // COMPLIANT - compound assignment, rule does not apply
+  l4 += l1;  // COMPLIANT - compound assignment, rule does not apply
+  l4 -= s32; // COMPLIANT - compound assignment, rule does not apply
 }