From 532c679ea9bdf337fa0c09cbc9b0737b4a4b1aa9 Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Wed, 16 Mar 2011 16:15:37 -0400 Subject: [PATCH] Core 1148 Core 1148 * typeck.c (check_return_expr): Fix conditions for setting LOOKUP_PREFER_RVALUE. From-SVN: r171071 --- gcc/cp/ChangeLog | 4 ++++ gcc/cp/typeck.c | 19 +++++++++++++------ gcc/testsuite/ChangeLog | 2 ++ gcc/testsuite/g++.dg/cpp0x/elision2.C | 13 +++++++++++++ 4 files changed, 32 insertions(+), 6 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/elision2.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 35d033758db..fe169832d2a 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,5 +1,9 @@ 2011-03-16 Jason Merrill + Core 1148 + * typeck.c (check_return_expr): Fix conditions for setting + LOOKUP_PREFER_RVALUE. + * call.c (build_over_call): Remove require_complete_type_sfinae call. PR c++/48132 diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c index 0e8a6d79b34..03aa49ee178 100644 --- a/gcc/cp/typeck.c +++ b/gcc/cp/typeck.c @@ -7760,12 +7760,19 @@ check_return_expr (tree retval, bool *no_warning) /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes treated as an rvalue for the purposes of overload resolution to - favor move constructors over copy constructors. */ - if ((cxx_dialect != cxx98) - && named_return_value_okay_p - /* The variable must not have the `volatile' qualifier. */ - && !CP_TYPE_VOLATILE_P (TREE_TYPE (retval)) - /* The return type must be a class type. */ + favor move constructors over copy constructors. + + Note that these conditions are similar to, but not as strict as, + the conditions for the named return value optimization. */ + if ((cxx_dialect != cxx98) + && (TREE_CODE (retval) == VAR_DECL + || TREE_CODE (retval) == PARM_DECL) + && DECL_CONTEXT (retval) == current_function_decl + && !TREE_STATIC (retval) + && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))), + (TYPE_MAIN_VARIANT + (TREE_TYPE (TREE_TYPE (current_function_decl))))) + /* This is only interesting for class type. */ && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))) flags = flags | LOOKUP_PREFER_RVALUE; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f5e7580c39d..5685b45576c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,7 @@ 2011-03-16 Jason Merrill + * g++.dg/cpp0x/elision2.C: New. + * g++.dg/cpp0x/constexpr-array3.C: New. 2011-03-16 Jason Merrill diff --git a/gcc/testsuite/g++.dg/cpp0x/elision2.C b/gcc/testsuite/g++.dg/cpp0x/elision2.C new file mode 100644 index 00000000000..216b1b59d16 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/elision2.C @@ -0,0 +1,13 @@ +// Core 1148: should be able to move from value parameter on return +// { dg-options -std=c++0x } + +struct A +{ + A(const A&) = delete; + A(A&&); +}; + +A f (A a) +{ + return a; +} -- 2.30.2