Added new testcase for known value outside integer range

Author: ceJce

test/testtype.cpp

@@ -478,6 +478,13 @@ class TestType : public TestFixture {
         check(code4, dinit(CheckOptions, $.settings = &settings));
         ASSERT_EQUALS("[test.cpp:2:5]: (style) int result is returned as long value. If the return value is long to avoid loss of information, then you have loss of information. [truncLongCastReturn]\n", errout_str());
 
+        const char code5[] = "long f() {\n"
+                             "    unsigned int n = 1U << 20;\n"
+                             "    return n << 20;\n"
+                             "}\n";
+        check(code5, dinit(CheckOptions, $.settings = &settings));
+        ASSERT_EQUALS("[test.cpp:3:5]: (style) int result is returned as long value. If the return value is long to avoid loss of information, then you have loss of information. [truncLongCastReturn]\n", errout_str());
+
         // typedef
         check("size_t f(int x, int y) {\n"
               "  return x * y;\n"