diff mbox series

[v19,14/40] c++: Implement __is_scoped_enum built-in trait

Message ID 20231013223957.1634024-15-kmatsui@gcc.gnu.org
State Unresolved
Headers
Series Optimize type traits performance |

Checks

Context Check Description
snail/gcc-patch-check warning Git am fail log

Commit Message

Ken Matsui Oct. 13, 2023, 10:37 p.m. UTC 
  This patch implements built-in trait for std::is_scoped_enum.

gcc/cp/ChangeLog:

	* cp-trait.def: Define __is_scoped_enum.
	* cp-trait.gperf: Reflect cp-trait.def change.
	* cp-trait.h: Likewise.
	* constraint.cc (diagnose_trait_expr): Handle CPTK_IS_SCOPED_ENUM.
	* semantics.cc (trait_expr_value): Likewise.
	(finish_trait_expr): Likewise.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/has-builtin-1.C: Test existence of __is_scoped_enum.
	* g++.dg/ext/is_scoped_enum.C: New test.

Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
---
 gcc/cp/constraint.cc                      |   3 +
 gcc/cp/cp-trait.def                       |   1 +
 gcc/cp/cp-trait.gperf                     |   1 +
 gcc/cp/cp-trait.h                         | 161 +++++++++++-----------
 gcc/cp/semantics.cc                       |   4 +
 gcc/testsuite/g++.dg/ext/has-builtin-1.C  |   3 +
 gcc/testsuite/g++.dg/ext/is_scoped_enum.C |  67 +++++++++
 7 files changed, 160 insertions(+), 80 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/ext/is_scoped_enum.C
diff mbox series

Patch

diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index d09252a56b6..1c0b2e0f178 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -3781,6 +3781,9 @@  diagnose_trait_expr (tree expr, tree args)
     case CPTK_IS_SAME:
       inform (loc, "  %qT is not the same as %qT", t1, t2);
       break;
+    case CPTK_IS_SCOPED_ENUM:
+      inform (loc, "  %qT is not a scoped enum", t1);
+      break;
     case CPTK_IS_STD_LAYOUT:
       inform (loc, "  %qT is not an standard layout type", t1);
       break;
diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
index 6d6dff7a4c3..e0e3fe1d23f 100644
--- a/gcc/cp/cp-trait.def
+++ b/gcc/cp/cp-trait.def
@@ -79,6 +79,7 @@  DEFTRAIT_EXPR (IS_POINTER_INTERCONVERTIBLE_BASE_OF, "__is_pointer_interconvertib
 DEFTRAIT_EXPR (IS_POD, "__is_pod", 1)
 DEFTRAIT_EXPR (IS_POLYMORPHIC, "__is_polymorphic", 1)
 DEFTRAIT_EXPR (IS_SAME, "__is_same", 2)
+DEFTRAIT_EXPR (IS_SCOPED_ENUM, "__is_scoped_enum", 1)
 DEFTRAIT_EXPR (IS_STD_LAYOUT, "__is_standard_layout", 1)
 DEFTRAIT_EXPR (IS_TRIVIAL, "__is_trivial", 1)
 DEFTRAIT_EXPR (IS_TRIVIALLY_ASSIGNABLE, "__is_trivially_assignable", 2)
diff --git a/gcc/cp/cp-trait.gperf b/gcc/cp/cp-trait.gperf
index 90fcdc01de6..f3fd82ba549 100644
--- a/gcc/cp/cp-trait.gperf
+++ b/gcc/cp/cp-trait.gperf
@@ -59,6 +59,7 @@  struct cp_trait {
 "__is_pod", CPTK_IS_POD, 1, false
 "__is_polymorphic", CPTK_IS_POLYMORPHIC, 1, false
 "__is_same", CPTK_IS_SAME, 2, false
+"__is_scoped_enum", CPTK_IS_SCOPED_ENUM, 1, false
 "__is_standard_layout", CPTK_IS_STD_LAYOUT, 1, false
 "__is_trivial", CPTK_IS_TRIVIAL, 1, false
 "__is_trivially_assignable", CPTK_IS_TRIVIALLY_ASSIGNABLE, 2, false
diff --git a/gcc/cp/cp-trait.h b/gcc/cp/cp-trait.h
index f22a6e93618..9c18165eb68 100644
--- a/gcc/cp/cp-trait.h
+++ b/gcc/cp/cp-trait.h
@@ -54,7 +54,7 @@  struct cp_trait {
   short arity;
   bool type;
 };
-/* maximum key range = 109, duplicates = 0 */
+/* maximum key range = 92, duplicates = 0 */
 
 class cp_trait_lookup
 {
@@ -69,32 +69,32 @@  cp_trait_lookup::hash (const char *str, size_t len)
 {
   static const unsigned char asso_values[] =
     {
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116,  20, 116,  45,   5,  20,
-       50,   0,  30,   5, 116,   0, 116, 116,   5,  10,
-       30,   0,   5, 116,  10,  30,   5,   0,  25, 116,
-      116,   5, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116, 116, 116, 116, 116,
-      116, 116, 116, 116, 116, 116
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 20, 99,  0,  5, 50,
+      30,  0, 40, 15, 99,  0, 99, 99,  5, 10,
+      30,  0,  5, 99, 10, 50,  5,  0, 35, 99,
+      99,  5, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+      99, 99, 99, 99, 99, 99
     };
   unsigned int hval = len;
 
@@ -116,56 +116,60 @@  cp_trait_lookup::find (const char *str, size_t len)
 {
   enum
     {
-      TOTAL_KEYWORDS = 50,
+      TOTAL_KEYWORDS = 51,
       MIN_WORD_LENGTH = 7,
       MAX_WORD_LENGTH = 37,
       MIN_HASH_VALUE = 7,
-      MAX_HASH_VALUE = 115
+      MAX_HASH_VALUE = 98
     };
 
   static const struct cp_trait wordlist[] =
     {
-#line 78 "../../gcc/cp/cp-trait.gperf"
+#line 79 "../../gcc/cp/cp-trait.gperf"
       {"__bases", CPTK_BASES, 1, true},
 #line 51 "../../gcc/cp/cp-trait.gperf"
       {"__is_enum", CPTK_IS_ENUM, 1, false},
-#line 68 "../../gcc/cp/cp-trait.gperf"
+#line 69 "../../gcc/cp/cp-trait.gperf"
       {"__is_union", CPTK_IS_UNION, 1, false},
-#line 72 "../../gcc/cp/cp-trait.gperf"
-      {"__remove_cv", CPTK_REMOVE_CV, 1, true},
 #line 73 "../../gcc/cp/cp-trait.gperf"
+      {"__remove_cv", CPTK_REMOVE_CV, 1, true},
+#line 74 "../../gcc/cp/cp-trait.gperf"
       {"__remove_cvref", CPTK_REMOVE_CVREF, 1, true},
 #line 50 "../../gcc/cp/cp-trait.gperf"
       {"__is_empty", CPTK_IS_EMPTY, 1, false},
-#line 63 "../../gcc/cp/cp-trait.gperf"
+#line 64 "../../gcc/cp/cp-trait.gperf"
       {"__is_trivial", CPTK_IS_TRIVIAL, 1, false},
-#line 74 "../../gcc/cp/cp-trait.gperf"
+#line 75 "../../gcc/cp/cp-trait.gperf"
       {"__remove_reference", CPTK_REMOVE_REFERENCE, 1, true},
-#line 79 "../../gcc/cp/cp-trait.gperf"
+#line 80 "../../gcc/cp/cp-trait.gperf"
       {"__direct_bases", CPTK_DIRECT_BASES, 1, true},
-#line 76 "../../gcc/cp/cp-trait.gperf"
+#line 42 "../../gcc/cp/cp-trait.gperf"
+      {"__is_array", CPTK_IS_ARRAY, 1, false},
+#line 77 "../../gcc/cp/cp-trait.gperf"
       {"__underlying_type", CPTK_UNDERLYING_TYPE, 1, true},
 #line 45 "../../gcc/cp/cp-trait.gperf"
       {"__is_bounded_array", CPTK_IS_BOUNDED_ARRAY, 1, false},
-#line 75 "../../gcc/cp/cp-trait.gperf"
+#line 76 "../../gcc/cp/cp-trait.gperf"
       {"__type_pack_element", CPTK_TYPE_PACK_ELEMENT, -1, true},
-#line 67 "../../gcc/cp/cp-trait.gperf"
+#line 68 "../../gcc/cp/cp-trait.gperf"
       {"__is_unbounded_array", CPTK_IS_UNBOUNDED_ARRAY, 1, false},
 #line 60 "../../gcc/cp/cp-trait.gperf"
       {"__is_polymorphic", CPTK_IS_POLYMORPHIC, 1, false},
 #line 54 "../../gcc/cp/cp-trait.gperf"
       {"__is_literal_type", CPTK_IS_LITERAL_TYPE, 1, false},
-#line 66 "../../gcc/cp/cp-trait.gperf"
+#line 67 "../../gcc/cp/cp-trait.gperf"
       {"__is_trivially_copyable", CPTK_IS_TRIVIALLY_COPYABLE, 1, false},
-#line 64 "../../gcc/cp/cp-trait.gperf"
+#line 41 "../../gcc/cp/cp-trait.gperf"
+      {"__is_aggregate", CPTK_IS_AGGREGATE, 1, false},
+#line 65 "../../gcc/cp/cp-trait.gperf"
       {"__is_trivially_assignable", CPTK_IS_TRIVIALLY_ASSIGNABLE, 2, false},
 #line 53 "../../gcc/cp/cp-trait.gperf"
       {"__is_layout_compatible", CPTK_IS_LAYOUT_COMPATIBLE, 2, false},
-#line 65 "../../gcc/cp/cp-trait.gperf"
+#line 66 "../../gcc/cp/cp-trait.gperf"
       {"__is_trivially_constructible", CPTK_IS_TRIVIALLY_CONSTRUCTIBLE, -1, false},
-#line 71 "../../gcc/cp/cp-trait.gperf"
+#line 72 "../../gcc/cp/cp-trait.gperf"
       {"__reference_converts_from_temporary", CPTK_REF_CONVERTS_FROM_TEMPORARY, 2, false},
-#line 70 "../../gcc/cp/cp-trait.gperf"
+#line 71 "../../gcc/cp/cp-trait.gperf"
       {"__reference_constructs_from_temporary", CPTK_REF_CONSTRUCTS_FROM_TEMPORARY, 2, false},
 #line 33 "../../gcc/cp/cp-trait.gperf"
       {"__has_nothrow_copy", CPTK_HAS_NOTHROW_COPY, 1, false},
@@ -173,22 +177,18 @@  cp_trait_lookup::find (const char *str, size_t len)
       {"__has_nothrow_assign", CPTK_HAS_NOTHROW_ASSIGN, 1, false},
 #line 58 "../../gcc/cp/cp-trait.gperf"
       {"__is_pointer_interconvertible_base_of", CPTK_IS_POINTER_INTERCONVERTIBLE_BASE_OF, 2, false},
-#line 69 "../../gcc/cp/cp-trait.gperf"
-      {"__is_volatile", CPTK_IS_VOLATILE, 1, false},
+#line 59 "../../gcc/cp/cp-trait.gperf"
+      {"__is_pod", CPTK_IS_POD, 1, false},
 #line 39 "../../gcc/cp/cp-trait.gperf"
       {"__has_virtual_destructor", CPTK_HAS_VIRTUAL_DESTRUCTOR, 1, false},
 #line 32 "../../gcc/cp/cp-trait.gperf"
       {"__has_nothrow_constructor", CPTK_HAS_NOTHROW_CONSTRUCTOR, 1, false},
-#line 44 "../../gcc/cp/cp-trait.gperf"
-      {"__is_base_of", CPTK_IS_BASE_OF, 2, false},
 #line 36 "../../gcc/cp/cp-trait.gperf"
       {"__has_trivial_copy", CPTK_HAS_TRIVIAL_COPY, 1, false},
-#line 61 "../../gcc/cp/cp-trait.gperf"
-      {"__is_same", CPTK_IS_SAME, 2, false},
 #line 34 "../../gcc/cp/cp-trait.gperf"
       {"__has_trivial_assign", CPTK_HAS_TRIVIAL_ASSIGN, 1, false},
-#line 30 "../../gcc/cp/cp-trait.gperf"
-      {"__is_same_as", CPTK_IS_SAME, 2, false},
+#line 70 "../../gcc/cp/cp-trait.gperf"
+      {"__is_volatile", CPTK_IS_VOLATILE, 1, false},
 #line 37 "../../gcc/cp/cp-trait.gperf"
       {"__has_trivial_destructor", CPTK_HAS_TRIVIAL_DESTRUCTOR, 1, false},
 #line 35 "../../gcc/cp/cp-trait.gperf"
@@ -197,47 +197,48 @@  cp_trait_lookup::find (const char *str, size_t len)
       {"__is_nothrow_assignable", CPTK_IS_NOTHROW_ASSIGNABLE, 2, false},
 #line 57 "../../gcc/cp/cp-trait.gperf"
       {"__is_nothrow_convertible", CPTK_IS_NOTHROW_CONVERTIBLE, 2, false},
-#line 47 "../../gcc/cp/cp-trait.gperf"
-      {"__is_const", CPTK_IS_CONST, 1, false},
-#line 56 "../../gcc/cp/cp-trait.gperf"
-      {"__is_nothrow_constructible", CPTK_IS_NOTHROW_CONSTRUCTIBLE, -1, false},
-#line 59 "../../gcc/cp/cp-trait.gperf"
-      {"__is_pod", CPTK_IS_POD, 1, false},
-#line 41 "../../gcc/cp/cp-trait.gperf"
-      {"__is_aggregate", CPTK_IS_AGGREGATE, 1, false},
-#line 42 "../../gcc/cp/cp-trait.gperf"
-      {"__is_array", CPTK_IS_ARRAY, 1, false},
-#line 49 "../../gcc/cp/cp-trait.gperf"
-      {"__is_convertible", CPTK_IS_CONVERTIBLE, 2, false},
-#line 48 "../../gcc/cp/cp-trait.gperf"
-      {"__is_constructible", CPTK_IS_CONSTRUCTIBLE, -1, false},
-#line 52 "../../gcc/cp/cp-trait.gperf"
-      {"__is_final", CPTK_IS_FINAL, 1, false},
 #line 46 "../../gcc/cp/cp-trait.gperf"
       {"__is_class", CPTK_IS_CLASS, 1, false},
-#line 38 "../../gcc/cp/cp-trait.gperf"
-      {"__has_unique_object_representations", CPTK_HAS_UNIQUE_OBJ_REPRESENTATIONS, 1, false},
+#line 56 "../../gcc/cp/cp-trait.gperf"
+      {"__is_nothrow_constructible", CPTK_IS_NOTHROW_CONSTRUCTIBLE, -1, false},
 #line 40 "../../gcc/cp/cp-trait.gperf"
       {"__is_abstract", CPTK_IS_ABSTRACT, 1, false},
 #line 43 "../../gcc/cp/cp-trait.gperf"
       {"__is_assignable", CPTK_IS_ASSIGNABLE, 2, false},
 #line 62 "../../gcc/cp/cp-trait.gperf"
+      {"__is_scoped_enum", CPTK_IS_SCOPED_ENUM, 1, false},
+#line 44 "../../gcc/cp/cp-trait.gperf"
+      {"__is_base_of", CPTK_IS_BASE_OF, 2, false},
+#line 61 "../../gcc/cp/cp-trait.gperf"
+      {"__is_same", CPTK_IS_SAME, 2, false},
+#line 63 "../../gcc/cp/cp-trait.gperf"
       {"__is_standard_layout", CPTK_IS_STD_LAYOUT, 1, false},
-#line 77 "../../gcc/cp/cp-trait.gperf"
-      {"__is_deducible ", CPTK_IS_DEDUCIBLE, 2, false}
+#line 30 "../../gcc/cp/cp-trait.gperf"
+      {"__is_same_as", CPTK_IS_SAME, 2, false},
+#line 78 "../../gcc/cp/cp-trait.gperf"
+      {"__is_deducible ", CPTK_IS_DEDUCIBLE, 2, false},
+#line 52 "../../gcc/cp/cp-trait.gperf"
+      {"__is_final", CPTK_IS_FINAL, 1, false},
+#line 38 "../../gcc/cp/cp-trait.gperf"
+      {"__has_unique_object_representations", CPTK_HAS_UNIQUE_OBJ_REPRESENTATIONS, 1, false},
+#line 47 "../../gcc/cp/cp-trait.gperf"
+      {"__is_const", CPTK_IS_CONST, 1, false},
+#line 49 "../../gcc/cp/cp-trait.gperf"
+      {"__is_convertible", CPTK_IS_CONVERTIBLE, 2, false},
+#line 48 "../../gcc/cp/cp-trait.gperf"
+      {"__is_constructible", CPTK_IS_CONSTRUCTIBLE, -1, false}
     };
 
   static const signed char lookup[] =
     {
       -1, -1, -1, -1, -1, -1, -1,  0, -1,  1,  2,  3, -1, -1,
-       4,  5, -1,  6,  7,  8, -1, -1,  9, 10, 11, 12, 13, 14,
-      15, -1, 16, -1, 17, 18, -1, 19, -1, 20, 21, -1, 22, -1,
-      23, 24, 25, 26, -1, 27, 28, 29, 30, -1, 31, -1, 32, 33,
-      -1, -1, 34, 35, 36, 37, -1, 38, 39, 40, 41, -1, 42, -1,
-      43, -1, -1, -1, -1, 44, -1, -1, -1, -1, -1, -1, -1, -1,
-      -1, 45, -1, -1, 46, -1, 47, -1, -1, -1, -1, 48, -1, -1,
-      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-      -1, -1, -1, 49
+       4,  5, -1,  6,  7,  8,  9, -1, 10, 11, 12, 13, 14, 15,
+      16, 17, 18, -1, 19, 20, -1, 21, -1, 22, 23, -1, 24, -1,
+      25, 26, 27, 28, -1, -1, 29, -1, 30, -1, -1, 31, 32, 33,
+      -1, -1, 34, 35, 36, 37, -1, 38, -1, 39, 40, 41, -1, 42,
+      43, -1, 44, -1, -1, 45, -1, -1, -1, -1, 46, -1, -1, -1,
+      -1, 47, -1, -1, -1, -1, 48, -1, -1, -1, -1, -1, 49, -1,
+      50
     };
 
   if (len <= MAX_WORD_LENGTH && len >= MIN_WORD_LENGTH)
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 32880754020..f56ab031d5f 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -12205,6 +12205,9 @@  trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_SAME:
       return same_type_p (type1, type2);
 
+    case CPTK_IS_SCOPED_ENUM:
+      return SCOPED_ENUM_P (type1);
+
     case CPTK_IS_STD_LAYOUT:
       return std_layout_type_p (type1);
 
@@ -12391,6 +12394,7 @@  finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_CONST:
     case CPTK_IS_ENUM:
     case CPTK_IS_SAME:
+    case CPTK_IS_SCOPED_ENUM:
     case CPTK_IS_UNBOUNDED_ARRAY:
     case CPTK_IS_UNION:
     case CPTK_IS_VOLATILE:
diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
index 4142da518b1..ba97beea3c3 100644
--- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
+++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
@@ -119,6 +119,9 @@ 
 #if !__has_builtin (__is_same_as)
 # error "__has_builtin (__is_same_as) failed"
 #endif
+#if !__has_builtin (__is_scoped_enum)
+# error "__has_builtin (__is_scoped_enum) failed"
+#endif
 #if !__has_builtin (__is_standard_layout)
 # error "__has_builtin (__is_standard_layout) failed"
 #endif
diff --git a/gcc/testsuite/g++.dg/ext/is_scoped_enum.C b/gcc/testsuite/g++.dg/ext/is_scoped_enum.C
new file mode 100644
index 00000000000..a563b6ee67d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/is_scoped_enum.C
@@ -0,0 +1,67 @@ 
+// { dg-do compile { target c++11 } }
+
+#include <testsuite_tr1.h>
+
+using namespace __gnu_test;
+
+#define SA(X) static_assert((X),#X)
+
+#define SA_TEST_FN(TRAIT, TYPE, EXPECT)	\
+  SA(TRAIT(TYPE) == EXPECT);			\
+  SA(TRAIT(const TYPE) == EXPECT);
+
+#define SA_TEST_CATEGORY(TRAIT, TYPE, EXPECT)	\
+  SA(TRAIT(TYPE) == EXPECT);					\
+  SA(TRAIT(const TYPE) == EXPECT);				\
+  SA(TRAIT(volatile TYPE) == EXPECT);			\
+  SA(TRAIT(const volatile TYPE) == EXPECT)
+
+enum class E { e1, e2 };
+SA_TEST_CATEGORY(__is_scoped_enum, E, true);
+enum class Ec : char { e1, e2 };
+SA_TEST_CATEGORY(__is_scoped_enum, Ec, true);
+
+// negative tests
+enum U { u1, u2 };
+SA_TEST_CATEGORY(__is_scoped_enum, U, false);
+enum F : int { f1, f2 };
+SA_TEST_CATEGORY(__is_scoped_enum, F, false);
+struct S;
+SA_TEST_CATEGORY(__is_scoped_enum, S, false);
+struct S { };
+SA_TEST_CATEGORY(__is_scoped_enum, S, false);
+
+SA_TEST_CATEGORY(__is_scoped_enum, int, false);
+SA_TEST_CATEGORY(__is_scoped_enum, int[], false);
+SA_TEST_CATEGORY(__is_scoped_enum, int[2], false);
+SA_TEST_CATEGORY(__is_scoped_enum, int[][2], false);
+SA_TEST_CATEGORY(__is_scoped_enum, int[2][3], false);
+SA_TEST_CATEGORY(__is_scoped_enum, int*, false);
+SA_TEST_CATEGORY(__is_scoped_enum, int&, false);
+SA_TEST_CATEGORY(__is_scoped_enum, int*&, false);
+SA_TEST_FN(__is_scoped_enum, int(), false);
+SA_TEST_FN(__is_scoped_enum, int(*)(), false);
+SA_TEST_FN(__is_scoped_enum, int(&)(), false);
+
+enum opaque_unscoped : short;
+enum class opaque_scoped;
+enum class opaque_scoped_with_base : long;
+
+SA_TEST_CATEGORY(__is_scoped_enum, opaque_unscoped, false);
+SA_TEST_CATEGORY(__is_scoped_enum, opaque_scoped, true);
+SA_TEST_CATEGORY(__is_scoped_enum, opaque_scoped_with_base, true);
+
+enum unscoped {
+  u_is_scoped = __is_scoped_enum(unscoped),
+};
+SA( ! unscoped::u_is_scoped );
+
+enum unscoped_fixed : char {
+  uf_is_scoped = __is_scoped_enum(unscoped_fixed),
+};
+SA( ! unscoped_fixed::uf_is_scoped );
+
+enum class scoped {
+  is_scoped = __is_scoped_enum(scoped),
+};
+SA( (bool) scoped::is_scoped );