diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc
index 6e0af863a49..1b2fd37c583 100644
--- a/gcc/c-family/c-common.cc
+++ b/gcc/c-family/c-common.cc
@@ -537,19 +537,14 @@ const struct c_common_resword c_common_reswords[] =
   { "volatile",		RID_VOLATILE,	0 },
   { "wchar_t",		RID_WCHAR,	D_CXXONLY },
   { "while",		RID_WHILE,	0 },
-  { "__is_assignable", RID_IS_ASSIGNABLE, D_CXXONLY },
-  { "__is_constructible", RID_IS_CONSTRUCTIBLE, D_CXXONLY },
-  { "__is_nothrow_assignable", RID_IS_NOTHROW_ASSIGNABLE, D_CXXONLY },
-  { "__is_nothrow_constructible", RID_IS_NOTHROW_CONSTRUCTIBLE, D_CXXONLY },
-  { "__is_convertible", RID_IS_CONVERTIBLE, D_CXXONLY },
-  { "__is_nothrow_convertible", RID_IS_NOTHROW_CONVERTIBLE, D_CXXONLY },
   { "__reference_constructs_from_temporary", RID_REF_CONSTRUCTS_FROM_TEMPORARY,
 					D_CXXONLY },
   { "__reference_converts_from_temporary", RID_REF_CONVERTS_FROM_TEMPORARY,
 					D_CXXONLY },
-  { "__remove_cv", RID_REMOVE_CV, D_CXXONLY },
-  { "__remove_reference", RID_REMOVE_REFERENCE, D_CXXONLY },
-  { "__remove_cvref", RID_REMOVE_CVREF, D_CXXONLY },
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+  { NAME, RID_##CODE, D_CXXONLY },
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
 
   /* C++ transactional memory.  */
   { "synchronized",	RID_SYNCHRONIZED, D_CXX_OBJC | D_TRANSMEM },
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index d5c98d306ce..b306815c23b 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -182,12 +182,12 @@ enum rid
   RID_IS_TRIVIALLY_ASSIGNABLE, RID_IS_TRIVIALLY_CONSTRUCTIBLE,
   RID_IS_TRIVIALLY_COPYABLE,
   RID_IS_UNION,                RID_UNDERLYING_TYPE,
-  RID_IS_ASSIGNABLE,           RID_IS_CONSTRUCTIBLE,
-  RID_IS_NOTHROW_ASSIGNABLE,   RID_IS_NOTHROW_CONSTRUCTIBLE,
-  RID_IS_CONVERTIBLE,		RID_IS_NOTHROW_CONVERTIBLE,
   RID_REF_CONSTRUCTS_FROM_TEMPORARY,
   RID_REF_CONVERTS_FROM_TEMPORARY,
-  RID_REMOVE_CV, RID_REMOVE_REFERENCE, RID_REMOVE_CVREF,
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+  RID_##CODE,
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
 
   /* C++11 */
   RID_CONSTEXPR, RID_DECLTYPE, RID_NOEXCEPT, RID_NULLPTR, RID_STATIC_ASSERT,
diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index ca73aff3f38..9323bb091e1 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -3714,9 +3714,10 @@ diagnose_trait_expr (tree expr, tree args)
     case CPTK_BASES:
     case CPTK_DIRECT_BASES:
     case CPTK_UNDERLYING_TYPE:
-    case CPTK_REMOVE_CV:
-    case CPTK_REMOVE_REFERENCE:
-    case CPTK_REMOVE_CVREF:
+#define DEFTRAIT_TYPE(CODE, NAME, ARITY) \
+    case CPTK_##CODE:
+#include "cp/cp-trait.def"
+#undef DEFTRAIT_TYPE
       /* We shouldn't see these non-expression traits.  */
       gcc_unreachable ();
     /* We deliberately omit the default case so that when adding a new
diff --git a/gcc/cp/cp-objcp-common.cc b/gcc/cp/cp-objcp-common.cc
index 2d3f206b530..bc397a5447f 100644
--- a/gcc/cp/cp-objcp-common.cc
+++ b/gcc/cp/cp-objcp-common.cc
@@ -458,18 +458,13 @@ names_builtin_p (const char *name)
     case RID_IS_TRIVIALLY_CONSTRUCTIBLE:
     case RID_IS_TRIVIALLY_COPYABLE:
     case RID_IS_UNION:
-    case RID_IS_ASSIGNABLE:
-    case RID_IS_CONSTRUCTIBLE:
-    case RID_IS_NOTHROW_ASSIGNABLE:
-    case RID_IS_NOTHROW_CONSTRUCTIBLE:
     case RID_UNDERLYING_TYPE:
-    case RID_IS_CONVERTIBLE:
-    case RID_IS_NOTHROW_CONVERTIBLE:
     case RID_REF_CONSTRUCTS_FROM_TEMPORARY:
     case RID_REF_CONVERTS_FROM_TEMPORARY:
-    case RID_REMOVE_CV:
-    case RID_REMOVE_REFERENCE:
-    case RID_REMOVE_CVREF:
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+    case RID_##CODE:
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
       return true;
     default:
       break;
diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
new file mode 100644
index 00000000000..817951f3e42
--- /dev/null
+++ b/gcc/cp/cp-trait.def
@@ -0,0 +1,37 @@
+#ifdef DEFTRAIT
+#define DEFTRAIT_EXPR(CODE, NAME, ARITY) DEFTRAIT(tcc_expression, CODE, NAME, ARITY)
+#define DEFTRAIT_TYPE(CODE, NAME, ARITY) DEFTRAIT(tcc_type, CODE, NAME, ARITY)
+#define DEFTRAIT_EXPR_DEFAULTED
+#define DEFTRAIT_TYPE_DEFAULTED
+#endif
+
+#ifndef DEFTRAIT_EXPR
+#define DEFTRAIT_EXPR(CODE, NAME, ARITY)
+#define DEFTRAIT_EXPR_DEFAULTED
+#endif
+
+#ifndef DEFTRAIT_TYPE
+#define DEFTRAIT_TYPE(CODE, NAME, ARITY)
+#define DEFTRAIT_TYPE_DEFAULTED
+#endif
+
+DEFTRAIT_EXPR (IS_ASSIGNABLE, "__is_assignable", 2)
+DEFTRAIT_EXPR (IS_NOTHROW_ASSIGNABLE, "__is_nothrow_assignable", 2)
+DEFTRAIT_EXPR (IS_CONSTRUCTIBLE, "__is_constructible", -1)
+DEFTRAIT_EXPR (IS_NOTHROW_CONSTRUCTIBLE, "__is_nothrow_constructible", -1)
+DEFTRAIT_EXPR (IS_CONVERTIBLE, "__is_convertible", 2)
+DEFTRAIT_EXPR (IS_NOTHROW_CONVERTIBLE, "__is_nothrow_convertible", 2)
+
+DEFTRAIT_TYPE (REMOVE_CV, "__remove_cv", 1)
+DEFTRAIT_TYPE (REMOVE_REFERENCE, "__remove_reference", 1)
+DEFTRAIT_TYPE (REMOVE_CVREF, "__remove_cvref", 1)
+
+#ifdef DEFTRAIT_EXPR_DEFAULTED
+#undef DEFTRAIT_EXPR
+#undef DEFTRAIT_EXPR_DEFAULTED
+#endif
+
+#ifdef DEFTRAIT_TYPE_DEFAULTED
+#undef DEFTRAIT_TYPE
+#undef DEFTRAIT_TYPE_DEFAULTED
+#endif
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 3cbcdf726ca..8c5a85ab5fe 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -1405,17 +1405,12 @@ enum cp_trait_kind
   CPTK_IS_TRIVIALLY_COPYABLE,
   CPTK_IS_UNION,
   CPTK_UNDERLYING_TYPE,
-  CPTK_IS_ASSIGNABLE,
-  CPTK_IS_CONSTRUCTIBLE,
-  CPTK_IS_NOTHROW_ASSIGNABLE,
-  CPTK_IS_NOTHROW_CONSTRUCTIBLE,
-  CPTK_IS_CONVERTIBLE,
-  CPTK_IS_NOTHROW_CONVERTIBLE,
   CPTK_REF_CONSTRUCTS_FROM_TEMPORARY,
   CPTK_REF_CONVERTS_FROM_TEMPORARY,
-  CPTK_REMOVE_CV,
-  CPTK_REMOVE_REFERENCE,
-  CPTK_REMOVE_CVREF,
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+  CPTK_##CODE,
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
 };
 
 /* The types that we are processing.  */
diff --git a/gcc/cp/cxx-pretty-print.cc b/gcc/cp/cxx-pretty-print.cc
index b91615439e4..a2ddbcb899a 100644
--- a/gcc/cp/cxx-pretty-print.cc
+++ b/gcc/cp/cxx-pretty-print.cc
@@ -2701,24 +2701,6 @@ pp_cxx_trait (cxx_pretty_printer *pp, tree t)
     case CPTK_IS_LITERAL_TYPE:
       pp_cxx_ws_string (pp, "__is_literal_type");
       break;
-    case CPTK_IS_ASSIGNABLE:
-      pp_cxx_ws_string (pp, "__is_assignable");
-      break;
-    case CPTK_IS_CONSTRUCTIBLE:
-      pp_cxx_ws_string (pp, "__is_constructible");
-      break;
-    case CPTK_IS_NOTHROW_ASSIGNABLE:
-      pp_cxx_ws_string (pp, "__is_nothrow_assignable");
-      break;
-    case CPTK_IS_NOTHROW_CONSTRUCTIBLE:
-      pp_cxx_ws_string (pp, "__is_nothrow_constructible");
-      break;
-    case CPTK_IS_CONVERTIBLE:
-      pp_cxx_ws_string (pp, "__is_convertible");
-      break;
-    case CPTK_IS_NOTHROW_CONVERTIBLE:
-      pp_cxx_ws_string (pp, "__is_nothrow_convertible");
-      break;
     case CPTK_REF_CONSTRUCTS_FROM_TEMPORARY:
       pp_cxx_ws_string (pp, "__reference_constructs_from_temporary");
       break;
@@ -2728,15 +2710,12 @@ pp_cxx_trait (cxx_pretty_printer *pp, tree t)
     case CPTK_UNDERLYING_TYPE:
       pp_cxx_ws_string (pp, "__underlying_type");
       break;
-    case CPTK_REMOVE_CV:
-      pp_cxx_ws_string (pp, "__remove_cv");
-      break;
-    case CPTK_REMOVE_REFERENCE:
-      pp_cxx_ws_string (pp, "__remove_reference");
-      break;
-    case CPTK_REMOVE_CVREF:
-      pp_cxx_ws_string (pp, "__remove_cvref");
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+    case CPTK_##CODE:			 \
+      pp_cxx_ws_string (pp, NAME);	 \
       break;
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
     default:
       gcc_unreachable ();
     }
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index d592d783250..138892716b4 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -1147,9 +1147,10 @@ cp_keyword_starts_decl_specifier_p (enum rid keyword)
       /* C++11 extensions.  */
     case RID_DECLTYPE:
     case RID_UNDERLYING_TYPE:
-    case RID_REMOVE_CV:
-    case RID_REMOVE_REFERENCE:
-    case RID_REMOVE_CVREF:
+#define DEFTRAIT_TYPE(CODE, NAME, ARITY) \
+    case RID_##CODE:
+#include "cp/cp-trait.def"
+#undef DEFTRAIT_TYPE
     case RID_CONSTEXPR:
       /* C++20 extensions.  */
     case RID_CONSTINIT:
@@ -5923,14 +5924,12 @@ cp_parser_primary_expression (cp_parser *parser,
 	case RID_IS_TRIVIALLY_CONSTRUCTIBLE:
 	case RID_IS_TRIVIALLY_COPYABLE:
 	case RID_IS_UNION:
-	case RID_IS_ASSIGNABLE:
-	case RID_IS_CONSTRUCTIBLE:
-	case RID_IS_NOTHROW_ASSIGNABLE:
-	case RID_IS_NOTHROW_CONSTRUCTIBLE:
-	case RID_IS_CONVERTIBLE:
-	case RID_IS_NOTHROW_CONVERTIBLE:
 	case RID_REF_CONSTRUCTS_FROM_TEMPORARY:
 	case RID_REF_CONVERTS_FROM_TEMPORARY:
+#define DEFTRAIT_EXPR(CODE, NAME, ARITY) \
+	case RID_##CODE:
+#include "cp/cp-trait.def"
+#undef DEFTRAIT_EXPR
 	  return cp_parser_trait (parser, token->keyword);
 
 	// C++ concepts
@@ -10998,30 +10997,6 @@ cp_parser_trait (cp_parser* parser, enum rid keyword)
     case RID_DIRECT_BASES:
       kind = CPTK_DIRECT_BASES;
       break;
-    case RID_IS_ASSIGNABLE:
-      kind = CPTK_IS_ASSIGNABLE;
-      binary = true;
-      break;
-    case RID_IS_CONSTRUCTIBLE:
-      kind = CPTK_IS_CONSTRUCTIBLE;
-      variadic = true;
-      break;
-    case RID_IS_NOTHROW_ASSIGNABLE:
-      kind = CPTK_IS_NOTHROW_ASSIGNABLE;
-      binary = true;
-      break;
-    case RID_IS_NOTHROW_CONSTRUCTIBLE:
-      kind = CPTK_IS_NOTHROW_CONSTRUCTIBLE;
-      variadic = true;
-      break;
-    case RID_IS_CONVERTIBLE:
-      kind = CPTK_IS_CONVERTIBLE;
-      binary = true;
-      break;
-    case RID_IS_NOTHROW_CONVERTIBLE:
-      kind = CPTK_IS_NOTHROW_CONVERTIBLE;
-      binary = true;
-      break;
     case RID_REF_CONSTRUCTS_FROM_TEMPORARY:
       kind = CPTK_REF_CONSTRUCTS_FROM_TEMPORARY;
       binary = true;
@@ -11030,18 +11005,15 @@ cp_parser_trait (cp_parser* parser, enum rid keyword)
       kind = CPTK_REF_CONVERTS_FROM_TEMPORARY;
       binary = true;
       break;
-    case RID_REMOVE_CV:
-      kind = CPTK_REMOVE_CV;
-      type = true;
-      break;
-    case RID_REMOVE_REFERENCE:
-      kind = CPTK_REMOVE_REFERENCE;
-      type = true;
-      break;
-    case RID_REMOVE_CVREF:
-      kind = CPTK_REMOVE_CVREF;
-      type = true;
+#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
+    case RID_##CODE:			 \
+      type = (TCC == tcc_type);		 \
+      kind = CPTK_##CODE;		 \
+      binary = (ARITY == 2);		 \
+      variadic = (ARITY == -1);		 \
       break;
+#include "cp/cp-trait.def"
+#undef DEFTRAIT
     default:
       gcc_unreachable ();
     }
@@ -19882,9 +19854,10 @@ cp_parser_simple_type_specifier (cp_parser* parser,
       return type;
 
     case RID_UNDERLYING_TYPE:
-    case RID_REMOVE_CV:
-    case RID_REMOVE_REFERENCE:
-    case RID_REMOVE_CVREF:
+#define DEFTRAIT_TYPE(CODE, NAME, ARITY) \
+    case RID_##CODE:
+#include "cp/cp-trait.def"
+#undef DEFTRAIT_TYPE
       type = cp_parser_trait (parser, token->keyword);
       if (decl_specs)
 	cp_parser_set_decl_spec_type (decl_specs, type,
