Index: clang/lib/Format/UnwrappedLineParser.cpp
===================================================================
--- clang/lib/Format/UnwrappedLineParser.cpp
+++ clang/lib/Format/UnwrappedLineParser.cpp
@@ -3085,6 +3085,13 @@
         return;
       break;
 
+// Get the type traits tokens. Let them behave like any other identifier (which
+// may also be a type trait).
+#define TYPE_TRAIT(N, I, K) case tok::kw_##I:
+#define ARRAY_TYPE_TRAIT(I, E, K) case tok::kw_##I:
+#define EXPRESSION_TRAIT(I, E, K) case tok::kw_##I:
+#include "clang/Basic/TokenKinds.def"
+
     case tok::identifier:
       // We need to differentiate identifiers for a template deduction guide,
       // variables, or function return types (the constraint expression has
Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -23743,6 +23743,15 @@
   verifyFormat("template <typename T>\n"
                "concept Node = std::is_object_v<T>;");
 
+  verifyFormat("template <class T>\n"
+               "concept integral = __is_integral(T);");
+
+  verifyFormat("template <class T>\n"
+               "concept is2D = __array_extent(T, 1) == 2;");
+
+  verifyFormat("template <class T>\n"
+               "concept isRhs = __is_rvalue_expr(std::declval<T>() + 2)");
+
   auto Style = getLLVMStyle();
   Style.BreakBeforeConceptDeclarations = FormatStyle::BBCDS_Allowed;