[PATCH v4 05/12] c++: Implement __remove_all_extents built-in trait

[Ken Matsui]

This patch implements built-in trait for std::remove_all_extents.

gcc/cp/ChangeLog:

        * cp-trait.def: Define __remove_all_extents.
        * semantics.cc (finish_trait_type): Handle
        CPTK_REMOVE_ALL_EXTENTS.

gcc/testsuite/ChangeLog:

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

Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org>
---
 gcc/cp/cp-trait.def                           |  1 +
 gcc/cp/semantics.cc                           |  3 +++
 gcc/testsuite/g++.dg/ext/has-builtin-1.C      |  3 +++
 gcc/testsuite/g++.dg/ext/remove_all_extents.C | 16 ++++++++++++++++
 4 files changed, 23 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/ext/remove_all_extents.C

diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
index 3ff5611b60e..ce29108bad6 100644
--- a/gcc/cp/cp-trait.def
+++ b/gcc/cp/cp-trait.def
@@ -94,6 +94,7 @@ DEFTRAIT_EXPR (IS_TRIVIALLY_COPYABLE, 
"__is_trivially_copyable", 1)
 DEFTRAIT_EXPR (IS_UNION, "__is_union", 1)
 DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, 
"__reference_constructs_from_temporary", 2)
 DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, 
"__reference_converts_from_temporary", 2)
+DEFTRAIT_TYPE (REMOVE_ALL_EXTENTS, "__remove_all_extents", 1)
 DEFTRAIT_TYPE (REMOVE_CV, "__remove_cv", 1)
 DEFTRAIT_TYPE (REMOVE_CVREF, "__remove_cvref", 1)
 DEFTRAIT_TYPE (REMOVE_EXTENT, "__remove_extent", 1)
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 6ab054b106a..c8ac5167c3c 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -12769,6 +12769,9 @@ finish_trait_type (cp_trait_kind kind, tree type1, tree 
type2,
        type1 = TREE_TYPE (type1);
       return build_pointer_type (type1);
 
+    case CPTK_REMOVE_ALL_EXTENTS:
+      return strip_array_types (type1);
+
     case CPTK_REMOVE_CV:
       return cv_unqualified (type1);
 
diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C 
b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
index 4f1094befb9..9af64173524 100644
--- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
+++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
@@ -164,6 +164,9 @@
 #if !__has_builtin (__reference_converts_from_temporary)
 # error "__has_builtin (__reference_converts_from_temporary) failed"
 #endif
+#if !__has_builtin (__remove_all_extents)
+# error "__has_builtin (__remove_all_extents) failed"
+#endif
 #if !__has_builtin (__remove_cv)
 # error "__has_builtin (__remove_cv) failed"
 #endif
diff --git a/gcc/testsuite/g++.dg/ext/remove_all_extents.C 
b/gcc/testsuite/g++.dg/ext/remove_all_extents.C
new file mode 100644
index 00000000000..60ade2ade7f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/remove_all_extents.C
@@ -0,0 +1,16 @@
+// { dg-do compile { target c++11 } }
+
+#define SA(X) static_assert((X),#X)
+
+class ClassType { };
+
+SA(__is_same(__remove_all_extents(int), int));
+SA(__is_same(__remove_all_extents(int[2]), int));
+SA(__is_same(__remove_all_extents(int[2][3]), int));
+SA(__is_same(__remove_all_extents(int[][3]), int));
+SA(__is_same(__remove_all_extents(const int[2][3]), const int));
+SA(__is_same(__remove_all_extents(ClassType), ClassType));
+SA(__is_same(__remove_all_extents(ClassType[2]), ClassType));
+SA(__is_same(__remove_all_extents(ClassType[2][3]), ClassType));
+SA(__is_same(__remove_all_extents(ClassType[][3]), ClassType));
+SA(__is_same(__remove_all_extents(const ClassType[2][3]), const ClassType));
-- 
2.43.0