diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index d9ddd36cec0d539c0f877c2c9b0861bd3258f5a9..1c675726f8ca51c9de98383a5958fb3905cd6702 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -1739,6 +1739,7 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, tsubst_flags_t complain) { conversion *conv = NULL; + conversion *bad_direct_conv = nullptr; tree to = TREE_TYPE (rto); tree from = rfrom; tree tfrom; @@ -1925,13 +1926,23 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags, complain); if (cand) - return cand->second_conv; + { + if (!cand->second_conv->bad_p) + return cand->second_conv; + + /* Direct reference binding wasn't successful and yielded a bad + conversion. Proceed with trying to go through a temporary + instead, and if that also fails then we'll return this bad + conversion rather than no conversion for sake of better + diagnostics. */ + bad_direct_conv = cand->second_conv; + } } /* From this point on, we conceptually need temporaries, even if we elide them. Only the cases above are "direct bindings". */ if (flags & LOOKUP_NO_TEMP_BIND) - return NULL; + return bad_direct_conv ? bad_direct_conv : nullptr; /* [over.ics.rank] @@ -1972,6 +1983,9 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, there's no strictly viable candidate. */ if (!maybe_valid_p && (flags & LOOKUP_SHORTCUT_BAD_CONVS)) { + if (bad_direct_conv) + return bad_direct_conv; + conv = alloc_conversion (ck_deferred_bad); conv->bad_p = true; return conv; @@ -1995,7 +2009,7 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, conv = implicit_conversion (to, from, expr, c_cast_p, flags, complain); if (!conv) - return NULL; + return bad_direct_conv ? bad_direct_conv : nullptr; if (conv->user_conv_p) { @@ -2018,7 +2032,7 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, = reference_binding (rto, ftype, NULL_TREE, c_cast_p, sflags, complain); if (!new_second) - return NULL; + return bad_direct_conv ? bad_direct_conv : nullptr; conv = merge_conversion_sequences (t, new_second); gcc_assert (maybe_valid_p || conv->bad_p); return conv; diff --git a/gcc/testsuite/g++.dg/cpp0x/rv-conv4.C b/gcc/testsuite/g++.dg/cpp0x/rv-conv4.C new file mode 100644 index 0000000000000000000000000000000000000000..7ecd2dc3ccdc9b0cf243463209c04635e5fb02fd --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/rv-conv4.C @@ -0,0 +1,16 @@ +// PR c++/113064 +// { dg-do compile { target c++11 } } + +struct B { }; + +struct A { + operator B() &; + operator B&&() &&; +}; + +void f(B&&); + +int main() { + A a; + f(a); +} diff --git a/gcc/testsuite/g++.dg/cpp0x/rv-conv5.C b/gcc/testsuite/g++.dg/cpp0x/rv-conv5.C new file mode 100644 index 0000000000000000000000000000000000000000..dcb6fc6f76f324bccaa8f0a5e2fcde1edaaa36c9 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/rv-conv5.C @@ -0,0 +1,23 @@ +// PR c++/113064 +// { dg-do compile { target c++11 } } + +struct no_copy { + no_copy() = default; + + no_copy(const no_copy&) = delete; + no_copy(no_copy&&); + + no_copy& operator=(const no_copy&) = delete; + no_copy& operator=(no_copy&&); +}; + +struct A { + operator no_copy() &; + operator no_copy&&() && = delete; +}; + +int main() { + no_copy nc; + A a; + nc = a; +}