diff options
| -rw-r--r-- | gcc/cp/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/cp/pt.c | 134 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp0x/variadic118.C | 3 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/template/dr1391-1.C | 17 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/template/dr1391-2.C | 22 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/template/dr1391-3.C | 13 |
6 files changed, 150 insertions, 43 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index f5a31fde12e..957dc1deed5 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,5 +1,9 @@ 2015-05-18 Jason Merrill <jason@redhat.com> + DR 1391 + * pt.c (type_unification_real): Check convertibility here. + (unify_one_argument): Not here. + * tree.c (strip_typedefs_expr) [TRAIT_EXPR]: Fix typo. (strip_typedefs) [DECLTYPE_TYPE]: Fix typedef of decltype. [TREE_LIST]: Fix no-change case. diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index 78714745452..2cd36c9c9ff 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -16678,7 +16678,7 @@ uses_deducible_template_parms (tree type) static int unify_one_argument (tree tparms, tree targs, tree parm, tree arg, - int subr, unification_kind_t strict, int flags, + int subr, unification_kind_t strict, bool explain_p) { tree arg_expr = NULL_TREE; @@ -16695,16 +16695,10 @@ unify_one_argument (tree tparms, tree targs, tree parm, tree arg, argument to convert it to the type of the corresponding function parameter if the parameter type contains no template-parameters that participate in template argument deduction. */ - if (TYPE_P (parm) && !uses_template_parms (parm)) - /* For function parameters that contain no template-parameters at all, - we have historically checked for convertibility in order to shortcut - consideration of this candidate. */ - return check_non_deducible_conversion (parm, arg, strict, flags, - explain_p); - else if (strict == DEDUCE_CALL - && TYPE_P (parm) && !uses_deducible_template_parms (parm)) - /* For function parameters with only non-deducible template parameters, - just return. */ + if (strict != DEDUCE_EXACT + && TYPE_P (parm) && !uses_deducible_template_parms (parm)) + /* For function parameters with no deducible template parameters, + just return. We'll check non-dependent conversions later. */ return unify_success (explain_p); switch (strict) @@ -16843,7 +16837,7 @@ type_unification_real (tree tparms, ++ia; if (unify_one_argument (tparms, targs, parm, arg, subr, strict, - flags, explain_p)) + explain_p)) return 1; } @@ -16925,8 +16919,11 @@ type_unification_real (tree tparms, this parameter can be deduced. */ if (TREE_CODE (tparm) == PARM_DECL && uses_template_parms (TREE_TYPE (tparm)) - && !saw_undeduced++) - goto again; + && saw_undeduced < 2) + { + saw_undeduced = 1; + continue; + } /* Core issue #226 (C++0x) [temp.deduct]: @@ -16937,32 +16934,9 @@ type_unification_real (tree tparms, be NULL_TREE or ERROR_MARK_NODE, so we do not need to explicitly check cxx_dialect here. */ if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i))) - { - tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i)); - tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i)); - reopen_deferring_access_checks (*checks); - location_t save_loc = input_location; - if (DECL_P (parm)) - input_location = DECL_SOURCE_LOCATION (parm); - arg = tsubst_template_arg (arg, targs, complain, NULL_TREE); - arg = convert_template_argument (parm, arg, targs, complain, - i, NULL_TREE); - input_location = save_loc; - *checks = get_deferred_access_checks (); - pop_deferring_access_checks (); - if (arg == error_mark_node) - return 1; - else - { - TREE_VEC_ELT (targs, i) = arg; - /* The position of the first default template argument, - is also the number of non-defaulted arguments in TARGS. - Record that. */ - if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs)) - SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i); - continue; - } - } + /* OK, there is a default argument. Wait until after the + conversion check to do substitution. */ + continue; /* If the type parameter is a parameter pack, then it will be deduced to an empty parameter pack. */ @@ -16987,6 +16961,84 @@ type_unification_real (tree tparms, return unify_parameter_deduction_failure (explain_p, tparm); } + + /* DR 1391: All parameters have args, now check non-dependent parms for + convertibility. */ + if (saw_undeduced < 2) + for (ia = 0, parms = xparms, args = xargs, nargs = xnargs; + parms && parms != void_list_node && ia < nargs; ) + { + parm = TREE_VALUE (parms); + + if (TREE_CODE (parm) == TYPE_PACK_EXPANSION + && (!TREE_CHAIN (parms) + || TREE_CHAIN (parms) == void_list_node)) + /* For a function parameter pack that occurs at the end of the + parameter-declaration-list, the type A of each remaining + argument of the call is compared with the type P of the + declarator-id of the function parameter pack. */ + break; + + parms = TREE_CHAIN (parms); + + if (TREE_CODE (parm) == TYPE_PACK_EXPANSION) + /* For a function parameter pack that does not occur at the + end of the parameter-declaration-list, the type of the + parameter pack is a non-deduced context. */ + continue; + + arg = args[ia]; + ++ia; + + if (uses_template_parms (parm)) + continue; + if (check_non_deducible_conversion (parm, arg, strict, flags, + explain_p)) + return 1; + } + + /* Now substitute into the default template arguments. */ + for (i = 0; i < ntparms; i++) + { + tree targ = TREE_VEC_ELT (targs, i); + tree tparm = TREE_VEC_ELT (tparms, i); + + if (targ || tparm == error_mark_node) + continue; + tree parm = TREE_VALUE (tparm); + + if (TREE_CODE (parm) == PARM_DECL + && uses_template_parms (TREE_TYPE (parm)) + && saw_undeduced < 2) + continue; + + tree arg = TREE_PURPOSE (tparm); + reopen_deferring_access_checks (*checks); + location_t save_loc = input_location; + if (DECL_P (parm)) + input_location = DECL_SOURCE_LOCATION (parm); + arg = tsubst_template_arg (arg, targs, complain, NULL_TREE); + arg = convert_template_argument (parm, arg, targs, complain, + i, NULL_TREE); + input_location = save_loc; + *checks = get_deferred_access_checks (); + pop_deferring_access_checks (); + if (arg == error_mark_node) + return 1; + else + { + TREE_VEC_ELT (targs, i) = arg; + /* The position of the first default template argument, + is also the number of non-defaulted arguments in TARGS. + Record that. */ + if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs)) + SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i); + continue; + } + } + + if (saw_undeduced++ == 1) + goto again; } #ifdef ENABLE_CHECKING if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs)) @@ -17601,7 +17653,7 @@ unify_pack_expansion (tree tparms, tree targs, tree packed_parms, /* Unify the pattern with the current argument. */ if (unify_one_argument (tparms, targs, parm, arg, subr, strict, - LOOKUP_IMPLICIT, explain_p)) + explain_p)) return 1; /* For each parameter pack, collect the deduced value. */ diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic118.C b/gcc/testsuite/g++.dg/cpp0x/variadic118.C index ee742ebb946..705e4e602dd 100644 --- a/gcc/testsuite/g++.dg/cpp0x/variadic118.C +++ b/gcc/testsuite/g++.dg/cpp0x/variadic118.C @@ -1,8 +1,7 @@ -// This should fail deduction, before it produces a candidate. // { dg-do compile { target c++11 } } template <class... T> -void f(T... ts); // { dg-message "deduction" } +void f(T... ts); struct B { }; int main() diff --git a/gcc/testsuite/g++.dg/template/dr1391-1.C b/gcc/testsuite/g++.dg/template/dr1391-1.C new file mode 100644 index 00000000000..0b99f5d4a91 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/dr1391-1.C @@ -0,0 +1,17 @@ +// DR 1391 + +template<class T> struct A { + typename T::N n; +}; +template<class T> struct B { }; + +template<class T, class T2> +void foo(const A<T>& r); // #1 +template<class T> +void foo(const B<T>& r); // #2 + +void baz() { + B<char> b; + foo(b); // OK + foo<char>(b); // error +} diff --git a/gcc/testsuite/g++.dg/template/dr1391-2.C b/gcc/testsuite/g++.dg/template/dr1391-2.C new file mode 100644 index 00000000000..1af71f0d333 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/dr1391-2.C @@ -0,0 +1,22 @@ +// DR 1391 +// { dg-do compile { target c++11 } } + +template<class T> +struct A { + typename T::N n; +}; + +template<class T> +struct B { }; + +template <class T, class... U> +typename A<T>::value_t bar(int, T, U...); + +template <class T> +T bar(T, T); + +void baz() +{ + B<char> b; + bar(b, b); +} diff --git a/gcc/testsuite/g++.dg/template/dr1391-3.C b/gcc/testsuite/g++.dg/template/dr1391-3.C new file mode 100644 index 00000000000..0f5879704c1 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/dr1391-3.C @@ -0,0 +1,13 @@ +// DR 1391 + +template <class T> struct Z { + typedef typename T::x xx; +}; +template <class T> typename Z<T>::xx f(void *, T); +template <class T> void f(int, T); +struct A {} a; +int main() { + f(1, a); // If the implementation rules out the first overload + // because of the invalid conversion from int to void*, + // the error instantiating Z<A> will be avoided +} |