diff options
Diffstat (limited to 'gcc/cp/constexpr.cc')
| -rw-r--r-- | gcc/cp/constexpr.cc | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index ee06858..1a77954 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -7736,13 +7736,24 @@ cxx_eval_store_expression (const constexpr_ctx *ctx, tree t, CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (*valp), first, NULL_TREE); /* Check for implicit change of active member for a union. */ + + /* LWG3436, CWG2675, c++/121068: The array object model is confused. For + now allow initializing an array element to activate the array. */ + auto only_array_refs = [](const releasing_vec &refs) + { + for (unsigned i = 1; i < refs->length(); i += 3) + if (TREE_CODE ((*refs)[i]) != INTEGER_CST) + return false; + return true; + }; + if (code == UNION_TYPE && (CONSTRUCTOR_NELTS (*valp) == 0 || CONSTRUCTOR_ELT (*valp, 0)->index != index) /* An INIT_EXPR of the last member in an access chain is always OK, but still check implicit change of members earlier on; see cpp2a/constexpr-union6.C. */ - && !(TREE_CODE (t) == INIT_EXPR && refs->is_empty ())) + && !(TREE_CODE (t) == INIT_EXPR && only_array_refs (refs))) { bool has_active_member = CONSTRUCTOR_NELTS (*valp) != 0; tree inner = strip_array_types (reftype); |