[PATCH v17 03/26] c++: Implement __is_volatile built-in trait

[Jason Merrill]

On 5/2/24 14:42, Ken Matsui wrote:
> This patch implements built-in trait for std::is_volatile.

OK.

> gcc/cp/ChangeLog:
> 
> 	* cp-trait.def: Define __is_volatile.
> 	* constraint.cc (diagnose_trait_expr): Handle CPTK_IS_VOLATILE.
> 	* semantics.cc (trait_expr_value): Likewise.
> 	(finish_trait_expr): Likewise.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/ext/has-builtin-1.C: Test existence of __is_volatile.
> 	* g++.dg/ext/is_volatile.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/semantics.cc                      |  4 ++++
>   gcc/testsuite/g++.dg/ext/has-builtin-1.C |  3 +++
>   gcc/testsuite/g++.dg/ext/is_volatile.C   | 20 ++++++++++++++++++++
>   5 files changed, 31 insertions(+)
>   create mode 100644 gcc/testsuite/g++.dg/ext/is_volatile.C
> 
> diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> index eaf17a50877..d9caf546423 100644
> --- a/gcc/cp/constraint.cc
> +++ b/gcc/cp/constraint.cc
> @@ -3862,6 +3862,9 @@ diagnose_trait_expr (tree expr, tree args)
>       case CPTK_IS_UNION:
>         inform (loc, "  %qT is not a union", t1);
>         break;
> +    case CPTK_IS_VOLATILE:
> +      inform (loc, "  %qT is not a volatile type", t1);
> +      break;
>       case CPTK_REF_CONSTRUCTS_FROM_TEMPORARY:
>         inform (loc, "  %qT is not a reference that binds to a temporary "
>   	      "object of type %qT (direct-initialization)", t1, t2);
> diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
> index 36faed9c0b3..e9347453829 100644
> --- a/gcc/cp/cp-trait.def
> +++ b/gcc/cp/cp-trait.def
> @@ -92,6 +92,7 @@ DEFTRAIT_EXPR (IS_TRIVIALLY_ASSIGNABLE, "__is_trivially_assignable", 2)
>   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_VOLATILE, "__is_volatile", 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_CV, "__remove_cv", 1)
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index fa7ba6a9edc..351235a639a 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -12616,6 +12616,9 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
>       case CPTK_IS_UNION:
>         return type_code1 == UNION_TYPE;
>   
> +    case CPTK_IS_VOLATILE:
> +      return CP_TYPE_VOLATILE_P (type1);
> +
>       case CPTK_REF_CONSTRUCTS_FROM_TEMPORARY:
>         return ref_xes_from_temporary (type1, type2, /*direct_init=*/true);
>   
> @@ -12826,6 +12829,7 @@ finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
>       case CPTK_IS_SAME:
>       case CPTK_IS_SCOPED_ENUM:
>       case CPTK_IS_UNION:
> +    case CPTK_IS_VOLATILE:
>         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 e3640faeb96..b2e2f2f694d 100644
> --- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> +++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> @@ -158,6 +158,9 @@
>   #if !__has_builtin (__is_union)
>   # error "__has_builtin (__is_union) failed"
>   #endif
> +#if !__has_builtin (__is_volatile)
> +# error "__has_builtin (__is_volatile) failed"
> +#endif
>   #if !__has_builtin (__reference_constructs_from_temporary)
>   # error "__has_builtin (__reference_constructs_from_temporary) failed"
>   #endif
> diff --git a/gcc/testsuite/g++.dg/ext/is_volatile.C b/gcc/testsuite/g++.dg/ext/is_volatile.C
> new file mode 100644
> index 00000000000..80a1cfc880d
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/ext/is_volatile.C
> @@ -0,0 +1,20 @@
> +// { dg-do compile { target c++11 } }
> +
> +#define SA(X) static_assert((X),#X)
> +
> +class ClassType { };
> +using cClassType = const ClassType;
> +using vClassType = volatile ClassType;
> +using cvClassType = const volatile ClassType;
> +
> +// Positive tests.
> +SA(__is_volatile(volatile int));
> +SA(__is_volatile(const volatile int));
> +SA(__is_volatile(vClassType));
> +SA(__is_volatile(cvClassType));
> +
> +// Negative tests.
> +SA(!__is_volatile(int));
> +SA(!__is_volatile(const int));
> +SA(!__is_volatile(ClassType));
> +SA(!__is_volatile(cClassType));