diff options
Diffstat (limited to 'gcc/cp/tree.c')
| -rw-r--r-- | gcc/cp/tree.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c index 97601aa..d7e9c7b 100644 --- a/gcc/cp/tree.c +++ b/gcc/cp/tree.c @@ -3570,6 +3570,30 @@ zero_init_p (const_tree t) return 1; } +/* Handle the C++17 [[nodiscard]] attribute, which is similar to the GNU + warn_unused_result attribute. */ + +static tree +handle_nodiscard_attribute (tree *node, tree name, tree /*args*/, + int /*flags*/, bool *no_add_attrs) +{ + if (TREE_CODE (*node) == FUNCTION_DECL) + { + if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (*node)))) + warning (OPT_Wattributes, "%qE attribute applied to %qD with void " + "return type", name, *node); + } + else if (OVERLOAD_TYPE_P (*node)) + /* OK */; + else + { + warning (OPT_Wattributes, "%qE attribute can only be applied to " + "functions or to class or enumeration types", name); + *no_add_attrs = true; + } + return NULL_TREE; +} + /* Table of valid C++ attributes. */ const struct attribute_spec cxx_attribute_table[] = { @@ -3591,6 +3615,8 @@ const struct attribute_spec std_attribute_table[] = affects_type_identity } */ { "maybe_unused", 0, 0, false, false, false, handle_unused_attribute, false }, + { "nodiscard", 0, 0, false, false, false, + handle_nodiscard_attribute, false }, { NULL, 0, 0, false, false, false, NULL, false } }; |