C++: Confirm correct behaviour on C++20

jbj · jbj · commit b2cd98a98f63 · 2020-08-24T13:42:40.000+02:00
Making `constexpr` imply `const` was correct for C++11 and was a correct
emulation of a GCC bug on GCC &lt; 5.0. This test confirms that the problem
isn't there in C++20.
diff --git a/cpp/ql/test/library-tests/specifiers2/cpp20.cpp b/cpp/ql/test/library-tests/specifiers2/cpp20.cpp
@@ -0,0 +1,10 @@
+// semmle-extractor-options: --edg --clang --edg --c++20
+
+namespace cpp20 {
+
+class TestConstexpr {
+    constexpr int member_constexpr() { return 0; } // not const in C++ >= 14
+    constexpr int member_const_constexpr() const { return 0; }
+};
+
+} // namespace cpp20
diff --git a/cpp/ql/test/library-tests/specifiers2/specifiers2.expected b/cpp/ql/test/library-tests/specifiers2/specifiers2.expected
@@ -1,5 +1,22 @@
 | Class | specifiers2pp.cpp:8:7:8:13 | MyClass | MyClass | abstract |
 | Class | specifiers2pp.cpp:24:7:24:14 | MyClass2 | MyClass2 | abstract |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | extern |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | extern |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | inline |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | inline |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | is_constexpr |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | is_constexpr |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | public |
+| Function | cpp20.cpp:5:7:5:7 | operator= | operator= | public |
+| Function | cpp20.cpp:6:19:6:34 | member_constexpr | member_constexpr | declared_constexpr |
+| Function | cpp20.cpp:6:19:6:34 | member_constexpr | member_constexpr | inline |
+| Function | cpp20.cpp:6:19:6:34 | member_constexpr | member_constexpr | is_constexpr |
+| Function | cpp20.cpp:6:19:6:34 | member_constexpr | member_constexpr | private |
+| Function | cpp20.cpp:7:19:7:40 | member_const_constexpr | member_const_constexpr | const |
+| Function | cpp20.cpp:7:19:7:40 | member_const_constexpr | member_const_constexpr | declared_constexpr |
+| Function | cpp20.cpp:7:19:7:40 | member_const_constexpr | member_const_constexpr | inline |
+| Function | cpp20.cpp:7:19:7:40 | member_const_constexpr | member_const_constexpr | is_constexpr |
+| Function | cpp20.cpp:7:19:7:40 | member_const_constexpr | member_const_constexpr | private |
 | Function | specifiers2.c:11:6:11:6 | f | f | extern |
 | Function | specifiers2.c:12:13:12:13 | f | f | extern |
 | Function | specifiers2.c:13:13:13:13 | f | f | extern |
diff --git a/cpp/ql/test/library-tests/specifiers2/specifiers2pp.cpp b/cpp/ql/test/library-tests/specifiers2/specifiers2pp.cpp
@@ -60,6 +60,6 @@ using Const_int = Const<int>;
 typedef volatile Const_int volatile_Const_int;
 
 class TestConstexpr {
-    constexpr int member_constexpr() { return 0; }
+    constexpr int member_constexpr() { return 0; } // const in C++11
     constexpr int member_const_constexpr() const { return 0; }
 };
