diff mbox series

[08/10] c++: implement __is_void built-in trait

Message ID 20230326043032.11096-9-kmatsui@cs.washington.edu
State New
Headers show
Series c++, libstdc++: get std::is_object to dispatch to new built-in traits | expand

Commit Message

Ken Matsui March 26, 2023, 4:30 a.m. UTC 
This patch implements built-in trait for std::is_void.

gcc/cp/ChangeLog:

	* cp-trait.def: Define __is_void.
	* constraint.cc (diagnose_trait_expr): Handle CPTK_IS_VOID.
	* semantics.cc (trait_expr_value): Likewise.
	(finish_trait_expr): Likewise.

gcc/testsuite/ChangeLog:

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

Signed-off-by: Ken Matsui <kmatsui@cs.washington.edu>
---
 gcc/cp/constraint.cc                     |  3 ++
 gcc/cp/cp-trait.def                      |  1 +
 gcc/cp/semantics.cc                      |  4 +++
 gcc/testsuite/g++.dg/ext/has-builtin-1.C |  3 ++
 gcc/testsuite/g++.dg/ext/is_void.C       | 35 ++++++++++++++++++++++++
 5 files changed, 46 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/ext/is_void.C
diff mbox series

Patch

diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index 500ac9177c7..e67c0ffeaac 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -3753,6 +3753,9 @@  diagnose_trait_expr (tree expr, tree args)
     case CPTK_IS_FUNCTION:
       inform (loc, "  %qT is not a function", t1);
       break;
+    case CPTK_IS_VOID:
+      inform (loc, "  %qT is not a void type", t1);
+      break;
     case CPTK_IS_AGGREGATE:
       inform (loc, "  %qT is not an aggregate", t1);
       break;
diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
index 99195201676..6284924630a 100644
--- a/gcc/cp/cp-trait.def
+++ b/gcc/cp/cp-trait.def
@@ -84,6 +84,7 @@  DEFTRAIT_EXPR (IS_TRIVIALLY_CONSTRUCTIBLE, "__is_trivially_constructible", -1)
 DEFTRAIT_EXPR (IS_TRIVIALLY_COPYABLE, "__is_trivially_copyable", 1)
 DEFTRAIT_EXPR (IS_UNION, "__is_union", 1)
 DEFTRAIT_EXPR (IS_FUNCTION, "__is_function", 1)
+DEFTRAIT_EXPR (IS_VOID, "__is_void", 1)
 DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, "__reference_constructs_from_temporary", 2)
 DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, "__reference_converts_from_temporary", 2)
 /* FIXME Added space to avoid direct usage in GCC 13.  */
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 36fe370da2d..a6598fedfbc 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -11996,6 +11996,9 @@  trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_FUNCTION:
       return type_code1 == FUNCTION_TYPE;
 
+    case CPTK_IS_VOID:
+      return VOID_TYPE_P (type1);
+
     case CPTK_IS_FINAL:
       return CLASS_TYPE_P (type1) && CLASSTYPE_FINAL (type1);
 
@@ -12209,6 +12212,7 @@  finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_SAME:
     case CPTK_IS_REFERENCE:
     case CPTK_IS_FUNCTION:
+    case CPTK_IS_VOID:
       break;
 
     case CPTK_IS_LAYOUT_COMPATIBLE:
diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
index 90eb00ebf2d..b96cc9e6f50 100644
--- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
+++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
@@ -152,3 +152,6 @@ 
 #if !__has_builtin (__is_function)
 # error "__has_builtin (__is_function) failed"
 #endif
+#if !__has_builtin (__is_void)
+# error "__has_builtin (__is_void) failed"
+#endif
diff --git a/gcc/testsuite/g++.dg/ext/is_void.C b/gcc/testsuite/g++.dg/ext/is_void.C
new file mode 100644
index 00000000000..707f0d6875b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/is_void.C
@@ -0,0 +1,35 @@ 
+// { dg-do compile { target c++11 } }
+
+#include <testsuite_tr1.h>
+
+using namespace __gnu_test;
+
+#define SA(X) static_assert((X),#X)
+#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)
+
+SA_TEST_CATEGORY(__is_void, void, true);
+
+SA_TEST_CATEGORY(__is_void, char, false);
+SA_TEST_CATEGORY(__is_void, signed char, false);
+SA_TEST_CATEGORY(__is_void, unsigned char, false);
+SA_TEST_CATEGORY(__is_void, wchar_t, false);
+SA_TEST_CATEGORY(__is_void, short, false);
+SA_TEST_CATEGORY(__is_void, unsigned short, false);
+SA_TEST_CATEGORY(__is_void, int, false);
+SA_TEST_CATEGORY(__is_void, unsigned int, false);
+SA_TEST_CATEGORY(__is_void, long, false);
+SA_TEST_CATEGORY(__is_void, unsigned long, false);
+SA_TEST_CATEGORY(__is_void, long long, false);
+SA_TEST_CATEGORY(__is_void, unsigned long long, false);
+SA_TEST_CATEGORY(__is_void, float, false);
+SA_TEST_CATEGORY(__is_void, double, false);
+SA_TEST_CATEGORY(__is_void, long double, false);
+
+// Sanity check.
+SA_TEST_CATEGORY(__is_void, ClassType, false);
+SA_TEST_CATEGORY(__is_void, IncompleteClass, false);
+SA_TEST_CATEGORY(__is_void, IncompleteUnion, false);