CPP:Make __is_trivial a builtin operation.

cpp/downgrades/dbe9c8eb5fc6f54b7ae08c7317d0795b24961564/upgrade.properties

@@ -0,0 +1,2 @@
+description: Make __is_trivial a builtin operation
+compatibility: full

cpp/ql/lib/semmle/code/cpp/exprs/BuiltInOperations.qll

@@ -1547,3 +1547,21 @@ class BuiltInBitCast extends BuiltInOperation, @builtinbitcast {
 
   override string getAPrimaryQlClass() { result = "BuiltInBitCast" }
 }
+
+/**
+ * A C++ `__is_trivial` built-in operation (used by some implementations of the
+ * `<type_traits>` header).
+ *
+ * Returns `true` if a type is a trivial type.
+ * ```
+ *  template<typename _Tp>
+ *    struct is_trivial
+ *    : public integral_constant<bool, __is_trivial(_Tp)>
+ *    {};
+ * ```
+ */
+class BuiltInIsTrivial extends BuiltInOperation, @istrivialexpr {
+  override string toString() { result = "__is_trivial" }
+
+  override string getAPrimaryQlClass() { result = "BuiltInIsTrivial" }
+}

cpp/ql/lib/semmlecode.cpp.dbscheme

@@ -1755,6 +1755,7 @@ case @expr.kind of
             | @istriviallydestructibleexpr
             | @istriviallyassignableexpr
             | @isnothrowassignableexpr
+            | @istrivialexpr
             | @isstandardlayoutexpr
             | @istriviallycopyableexpr
             | @isliteraltypeexpr

cpp/ql/lib/upgrades/d77c09d8bdc172c9201dec293de1e14c931d3f05/upgrade.properties

@@ -0,0 +1,2 @@
+description: Make __is_trivial a builtin operation
+compatibility: full

cpp/ql/test/library-tests/builtins/type_traits/clang.cpp

@@ -86,3 +86,10 @@ bool bok_is_void2 = __is_void(int);
 
 bool bok_is_volatile1 = __is_volatile(volatile int);
 bool bok_is_volatile2 = __is_volatile(int);
+
+struct S2 {
+    S2() {}
+};
+
+bool bok_is_trivial1 = __is_trivial(int);
+bool bok_is_trivial2 = __is_trivial(S2);

cpp/ql/test/library-tests/builtins/type_traits/expr.expected

@@ -121,6 +121,10 @@
 | clang.cpp:87:25:87:51 | volatile int |  | <none> |
 | clang.cpp:88:25:88:42 | __is_volatile | int | 0 |
 | clang.cpp:88:25:88:42 | int |  | <none> |
+| clang.cpp:94:24:94:40 | __is_trivial | int | 1 |
+| clang.cpp:94:24:94:40 | int |  | <none> |
+| clang.cpp:95:24:95:39 | S2 |  | <none> |
+| clang.cpp:95:24:95:39 | __is_trivial | S2 | 0 |
 | file://:0:0:0:0 | 0 |  | 0 |
 | file://:0:0:0:0 | 1 |  | 1 |
 | file://:0:0:0:0 | 2 |  | 2 |