add test

Author: ludviggunne

test/testunusedvar.cpp

@@ -156,6 +156,7 @@ class TestUnusedVar : public TestFixture {
         TEST_CASE(localvar70);
         TEST_CASE(localvar71);
         TEST_CASE(localvar72);
+        TEST_CASE(localvar73);
         TEST_CASE(localvarloops); // loops
         TEST_CASE(localvaralias1);
         TEST_CASE(localvaralias2); // ticket #1637
@@ -4074,6 +4075,16 @@ class TestUnusedVar : public TestFixture {
         ASSERT_EQUALS("[test.cpp:4:12]: (style) Unused variable: mp [unusedVariable]\n", errout_str());
     }
 
+    void localvar73() {
+        functionVariableUsage("struct S { S(); ~S(); };\n"
+                              "void f() {\n"
+                              "    auto a{ S() };\n"
+                              "    auto const &b{ S() };\n"
+                              "    const auto &&c{ S() };\n"
+                              "}\n");
+        ASSERT_EQUALS("", errout_str());
+    }
+
     void localvarloops() {
         // loops
         functionVariableUsage("void fun(int c) {\n"