CPP: Add test coverage for isModifiedByArithmeticOperation.

Author: geoffw0

cpp/ql/test/query-tests/Likely Bugs/Leap Year/UncheckedLeapYearAfterYearModification/UncheckedLeapYearAfterYearModification.expected

@@ -9,3 +9,7 @@
 | test.cpp:636:11:636:17 | tm_year | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:56:6:56:12 | tm_year | tm_year | test.cpp:628:12:628:19 | timeinfo | timeinfo |
 | test.cpp:640:5:640:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:629:13:629:14 | st | st |
 | test.cpp:642:5:642:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:629:13:629:14 | st | st |
+| test.cpp:718:5:718:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:712:13:712:14 | st | st |
+| test.cpp:731:5:731:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:725:13:725:14 | st | st |
+| test.cpp:732:5:732:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:725:13:725:14 | st | st |
+| test.cpp:733:5:733:9 | wYear | Field $@ on variable $@ has been modified, but no appropriate check for LeapYear was found. | test.cpp:12:7:12:11 | wYear | wYear | test.cpp:725:13:725:14 | st | st |

cpp/ql/test/query-tests/Likely Bugs/Leap Year/UncheckedLeapYearAfterYearModification/UncheckedReturnValueForTimeFunctions.expected

@@ -1,3 +1,5 @@
 | test.cpp:317:2:317:21 | call to SystemTimeToFileTime | Return value of $@ function should be verified to check for any error because variable $@ is not guaranteed to be safe. | test.cpp:63:1:63:20 | SystemTimeToFileTime | SystemTimeToFileTime | test.cpp:309:13:309:14 | st | st |
 | test.cpp:330:2:330:21 | call to SystemTimeToFileTime | Return value of $@ function should be verified to check for any error because variable $@ is not guaranteed to be safe. | test.cpp:63:1:63:20 | SystemTimeToFileTime | SystemTimeToFileTime | test.cpp:322:13:322:14 | st | st |
 | test.cpp:341:2:341:21 | call to SystemTimeToFileTime | Return value of $@ function should be verified to check for any error because variable $@ is not guaranteed to be safe. | test.cpp:63:1:63:20 | SystemTimeToFileTime | SystemTimeToFileTime | test.cpp:333:62:333:63 | st | st |
+| test.cpp:720:2:720:21 | call to SystemTimeToFileTime | Return value of $@ function should be verified to check for any error because variable $@ is not guaranteed to be safe. | test.cpp:63:1:63:20 | SystemTimeToFileTime | SystemTimeToFileTime | test.cpp:712:13:712:14 | st | st |
+| test.cpp:735:2:735:21 | call to SystemTimeToFileTime | Return value of $@ function should be verified to check for any error because variable $@ is not guaranteed to be safe. | test.cpp:63:1:63:20 | SystemTimeToFileTime | SystemTimeToFileTime | test.cpp:725:13:725:14 | st | st |

cpp/ql/test/query-tests/Likely Bugs/Leap Year/UncheckedLeapYearAfterYearModification/test.cpp

@@ -680,3 +680,57 @@ void mkDateTest(int year)
 	}
 	// ...
 }
+
+void unmodified1()
+{
+	SYSTEMTIME st;
+	FILETIME ft;
+	WORD w;
+
+	GetSystemTime(&st);
+
+	w = st.wYear;
+
+	SystemTimeToFileTime(&st, &ft); // GOOD - no modification
+}
+
+void unmodified2()
+{
+	SYSTEMTIME st;
+	FILETIME ft;
+	WORD *w_ptr;
+
+	GetSystemTime(&st);
+
+	w_ptr = &(st.wYear);
+
+	SystemTimeToFileTime(&st, &ft); // GOOD - no modification
+}
+
+void modified3()
+{
+	SYSTEMTIME st;
+	FILETIME ft;
+	WORD *w_ptr;
+
+	GetSystemTime(&st);
+
+	st.wYear = st.wYear + 1;
+
+	SystemTimeToFileTime(&st, &ft); // BAD
+}
+
+void modified4()
+{
+	SYSTEMTIME st;
+	FILETIME ft;
+	WORD *w_ptr;
+
+	GetSystemTime(&st);
+
+	st.wYear++;
+	st.wYear++;
+	st.wYear++;
+
+	SystemTimeToFileTime(&st, &ft); // BAD
+}