diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cp/call.cc | 9 | ||||
| -rw-r--r-- | gcc/cp/cp-tree.h | 1 | ||||
| -rw-r--r-- | gcc/cp/cvt.cc | 13 | ||||
| -rw-r--r-- | gcc/cp/typeck.cc | 10 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp0x/temp-extend3.C | 32 |
5 files changed, 55 insertions, 10 deletions
diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index c1c8987..b1469cb 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -10828,10 +10828,8 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) if (is_really_empty_class (type, /*ignore_vptr*/true)) { /* Avoid copying empty classes, but ensure op= returns an lvalue even - if the object argument isn't one. This isn't needed in other cases - since MODIFY_EXPR is always considered an lvalue. */ - to = cp_build_addr_expr (to, tf_none); - to = cp_build_indirect_ref (input_location, to, RO_ARROW, complain); + if the object argument isn't one. */ + to = force_lvalue (to, complain); val = build2 (COMPOUND_EXPR, type, arg, to); suppress_warning (val, OPT_Wunused); } @@ -10852,6 +10850,9 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) tree array_type, alias_set; arg2 = TYPE_SIZE_UNIT (as_base); + /* Ensure op= returns an lvalue even if the object argument isn't + one. */ + to = force_lvalue (to, complain); to = cp_stabilize_reference (to); arg0 = cp_build_addr_expr (to, complain); diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 2f2122d..927f51b 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -7079,6 +7079,7 @@ extern tree convert_to_reference (tree, tree, int, int, tree, tsubst_flags_t); extern tree convert_from_reference (tree); extern tree force_rvalue (tree, tsubst_flags_t); +extern tree force_lvalue (tree, tsubst_flags_t); extern tree ocp_convert (tree, tree, int, int, tsubst_flags_t); extern tree cp_convert (tree, tree, tsubst_flags_t); diff --git a/gcc/cp/cvt.cc b/gcc/cp/cvt.cc index bd1f147..f663a6d 100644 --- a/gcc/cp/cvt.cc +++ b/gcc/cp/cvt.cc @@ -575,6 +575,19 @@ force_rvalue (tree expr, tsubst_flags_t complain) return expr; } +/* Force EXPR to be an lvalue, if it isn't already. */ + +tree +force_lvalue (tree expr, tsubst_flags_t complain) +{ + if (!lvalue_p (expr)) + { + expr = cp_build_addr_expr (expr, complain); + expr = cp_build_indirect_ref (input_location, expr, RO_ARROW, complain); + } + return expr; +} + /* If EXPR and ORIG are INTEGER_CSTs, return a version of EXPR that has TREE_OVERFLOW set only if it is set in ORIG. Otherwise, return EXPR diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc index c8e4441..88f8f34 100644 --- a/gcc/cp/typeck.cc +++ b/gcc/cp/typeck.cc @@ -3870,13 +3870,11 @@ cp_build_indirect_ref_1 (location_t loc, tree ptr, ref_operator errorstring, return error_mark_node; } else if (do_fold && TREE_CODE (pointer) == ADDR_EXPR - && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))) - /* Don't let this change the value category. '*&TARGET_EXPR' - is an lvalue, but folding it into 'TARGET_EXPR' would turn - it into a prvalue of class type. */ - && lvalue_p (TREE_OPERAND (pointer, 0))) + && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0)))) /* The POINTER was something like `&x'. We simplify `*&x' to - `x'. */ + `x'. This can change the value category: '*&TARGET_EXPR' + is an lvalue and folding it into 'TARGET_EXPR' turns it into + a prvalue of class type. */ return TREE_OPERAND (pointer, 0); else { diff --git a/gcc/testsuite/g++.dg/cpp0x/temp-extend3.C b/gcc/testsuite/g++.dg/cpp0x/temp-extend3.C new file mode 100644 index 0000000..3eab88d --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/temp-extend3.C @@ -0,0 +1,32 @@ +// PR c++/119383 +// { dg-do run { target c++11 } } + +int g; + +struct base { + virtual base *clone() const = 0; + ~base() { } +}; + +struct impl : virtual base { + base *clone() const { return new impl; } // #1 + impl() { ++g; } + ~impl() { --g; } +}; + +const base * +make_a_clone () +{ + const base &base = impl{}; // #2 + return base.clone(); +} + +int +main () +{ + make_a_clone (); + // impl::impl() is called twice (#1 and #2), impl::~impl() once, + // at the end of make_a_clone. + if (g != 1) + __builtin_abort (); +} |