diff options
Diffstat (limited to 'gcc/cp/class.c')
| -rw-r--r-- | gcc/cp/class.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/gcc/cp/class.c b/gcc/cp/class.c index e6d5bb0..2c5ce73 100644 --- a/gcc/cp/class.c +++ b/gcc/cp/class.c @@ -214,6 +214,7 @@ static bool base_derived_from (tree, tree); static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree); static tree end_of_base (tree); static tree get_vcall_index (tree, tree); +static bool type_maybe_constexpr_default_constructor (tree); /* Variables shared between class.c and call.c. */ @@ -3346,7 +3347,11 @@ add_implicitly_declared_members (tree t, tree* access_decls, CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1; if (cxx_dialect >= cxx11) TYPE_HAS_CONSTEXPR_CTOR (t) - = type_has_constexpr_default_constructor (t); + /* Don't force the declaration to get a hard answer; if the + definition would have made the class non-literal, it will still be + non-literal because of the base or member in question, and that + gives a better diagnostic. */ + = type_maybe_constexpr_default_constructor (t); } /* [class.ctor] @@ -5348,16 +5353,28 @@ type_has_constexpr_default_constructor (tree t) { if (!TYPE_HAS_COMPLEX_DFLT (t)) return trivial_default_constructor_is_constexpr (t); - /* Assume it's constexpr to avoid unnecessary instantiation; if the - definition would have made the class non-literal, it will still be - non-literal because of the base or member in question, and that - gives a better diagnostic. */ - return true; + /* Non-trivial, we need to check subobject constructors. */ + lazily_declare_fn (sfk_constructor, t); } fns = locate_ctor (t); return (fns && DECL_DECLARED_CONSTEXPR_P (fns)); } +/* Returns true iff class T has a constexpr default constructor or has an + implicitly declared default constructor that we can't tell if it's constexpr + without forcing a lazy declaration (which might cause undesired + instantiations). */ + +bool +type_maybe_constexpr_default_constructor (tree t) +{ + if (CLASS_TYPE_P (t) && CLASSTYPE_LAZY_DEFAULT_CTOR (t) + && TYPE_HAS_COMPLEX_DFLT (t)) + /* Assume it's constexpr. */ + return true; + return type_has_constexpr_default_constructor (t); +} + /* Returns true iff class TYPE has a virtual destructor. */ bool |