| Message ID | 20221206175702.987794-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: NTTP object wrapper substitution fixes [PR103346, ...] | expand |
On Tue, 6 Dec 2022, Patrick Palka wrote: > This patch fixes some issues with substitution into a C++20 template > parameter object wrapper: > > * The first testcase demonstrates a situation where the same_type_p > assert in relevant case of tsubst_copy doesn't hold, because (partial) > substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields > A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a > nop and yields A<T> due to tsubst's level == 1 early exit test. So > this patch just gets rid of the assert; the type mismatch doesn't > seem to be a problem in practice since the coercion is from one > dependent type to another. > > * In the second testcase, dependent substitution into the underlying > TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which > tsubst_copy doesn't expect. This patch fixes this by handling empty > TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after > this substitution we're left with a VIEW_CONVERT_EXPR wrapping a > CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent > non-dependent substitution tsubst_copy doesn't expect either. So > this patch also relaxes the tsubst_copy case to accept such > VIEW_CONVERT_EXPR too. > > * In the third testcase, we end up never resolving the call to > f.modify() since tsubst_copy doesn't do overload resolution. > This patch fixes this by moving the handling of these > VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. > And it turns out (at least according to our testsuite) that > tsubst_copy doesn't directly need to handle the other kinds of > NON_LVALUE_EXPR and VIEW_CONVERT_EXPR, so this patch also gets rid > of the location_wrapper_p handling from tsubst_copy and moves the > REF_PARENTHESIZED_P handling to tsubst_copy_and_build. On second thought, getting rid of the location_wrapper_p and REF_PARENTHESIZED_P handling from tsubst_copy is perhaps too risky at this stage. The following patch instead just moves the tparm object wrapper handling from tsubst_copy to tsubst_copy_and_build and leaves the rest of tsubst_copy alone. Smoke tested so far, full bootstrap+regtest in progress: -- >8-- Subject: [PATCH] c++: NTTP object wrapper substitution fixes [PR103346, ...] This patch fixes some issues with substitution into a C++20 template parameter object wrapper: * The first testcase demonstrates a situation where the same_type_p assert in relevant case of tsubst_copy doesn't hold, because (partial) substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a nop and yields A<T> due to tsubst's level == 1 early exit test. So this patch just gets rid of the assert; the type mismatch doesn't seem to be a problem in practice, I suppose because the coercion is from one dependent type to another. * In the second testcase, dependent substitution into the underlying TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which tsubst_copy doesn't expect. This patch fixes this by handling empty TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after this substitution we're left with a VIEW_CONVERT_EXPR wrapping a CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent non-dependent substitution tsubst_copy doesn't expect either. So this patch also relaxes tsubst_copy to accept such VIEW_CONVERT_EXPR too. * In the third testcase, we end up never resolving the call to f.modify() since tsubst_copy doesn't do overload resolution. This patch fixes this by moving the handling of these VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. For good measure tsubst_copy_and_build should also handle REF_PARENTHESIZED_P wrappers instead of delegating to tsubst_copy. After this patch, VIEW_CONVERT_EXPR substitution is ultimately just moved from tsubst_copy to tsubst_copy_and_build and made more permissive. Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for trunk? PR c++/103346 PR c++/104278 PR c++/102553 gcc/cp/ChangeLog: * pt.cc (tsubst_copy) <case VIEW_CONVERT_EXPR>: In the handling of C++20 template parameter object wrappers: Remove same_type_p assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle empty TREE_TYPE on substituted inner operand. Move it to ... (tsubst_copy_and_build): ... here. Also handle REF_PARENTHESIZED_P VIEW_CONVERT_EXPRs. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/nontype-class52a.C: New test. * g++.dg/cpp2a/nontype-class53.C: New test. * g++.dg/cpp2a/nontype-class54.C: New test. * g++.dg/cpp2a/nontype-class55.C: New test. --- gcc/cp/pt.cc | 73 ++++++++++--------- gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 ++++ gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++++ gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++++ gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 ++++ 5 files changed, 116 insertions(+), 35 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index 2d8e4fdd4b5..0a196f069ad 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -17271,42 +17271,16 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); } tree op = TREE_OPERAND (t, 0); - if (code == VIEW_CONVERT_EXPR - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) - { - /* Wrapper to make a C++20 template parameter object const. */ - op = tsubst_copy (op, args, complain, in_decl); - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) - { - /* The template argument is not const, presumably because - it is still dependent, and so not the const template parm - object. */ - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); - gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p - (type, TREE_TYPE (op))); - if (TREE_CODE (op) == CONSTRUCTOR - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) - { - /* Don't add a wrapper to these. */ - op = copy_node (op); - TREE_TYPE (op) = type; - } - else - /* Do add a wrapper otherwise (in particular, if op is - another TEMPLATE_PARM_INDEX). */ - op = build1 (code, type, op); - } - return op; - } /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) + if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) { op = tsubst_copy (op, args, complain, in_decl); op = build1 (code, TREE_TYPE (op), op); REF_PARENTHESIZED_P (op) = true; return op; } - /* We shouldn't see any other uses of these in templates. */ + /* We shouldn't see any other uses of these in templates + (tsubst_copy_and_build handles C++20 tparm object wrappers). */ gcc_unreachable (); } @@ -21569,12 +21543,41 @@ tsubst_copy_and_build (tree t, case NON_LVALUE_EXPR: case VIEW_CONVERT_EXPR: - if (location_wrapper_p (t)) - /* We need to do this here as well as in tsubst_copy so we get the - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), - EXPR_LOCATION (t))); - /* fallthrough. */ + { + tree op = RECUR (TREE_OPERAND (t, 0)); + if (location_wrapper_p (t)) + /* We need to do this here as well as in tsubst_copy so we get the + other tsubst_copy_and_build semantics for a PARM_DECL operand. */ + RETURN (maybe_wrap_with_location (op, EXPR_LOCATION (t))); + + gcc_checking_assert (TREE_CODE (t) == VIEW_CONVERT_EXPR); + if (REF_PARENTHESIZED_P (t)) + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ + RETURN (finish_parenthesized_expr (op)); + + /* Otherwise, we're dealing with a wrapper to make a C++20 template + parameter object const. */ + if (TREE_TYPE (op) == NULL_TREE + || !CP_TYPE_CONST_P (TREE_TYPE (op))) + { + /* The template argument is not const, presumably because + it is still dependent, and so not the const template parm + object. */ + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); + if (TREE_CODE (op) == CONSTRUCTOR + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) + { + /* Don't add a wrapper to these. */ + op = copy_node (op); + TREE_TYPE (op) = type; + } + else + /* Do add a wrapper otherwise (in particular, if op is + another TEMPLATE_PARM_INDEX). */ + op = build1 (VIEW_CONVERT_EXPR, type, op); + } + RETURN (op); + } default: /* Handle Objective-C++ constructs, if appropriate. */ diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C new file mode 100644 index 00000000000..ae5d5df70ac --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C @@ -0,0 +1,15 @@ +// A version of nontype-class52.C where explicit template arguments are +// given in the call to f (which during deduction need to be partially +// substituted into the NTTP object V in f's signature). +// { dg-do compile { target c++20 } } + +template<class> struct A { }; + +template<auto> struct B { }; + +template<class T, A<T> V> void f(B<V>); + +int main() { + constexpr A<int> a; + f<int>(B<a>{}); +} diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C new file mode 100644 index 00000000000..9a6398c5f57 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C @@ -0,0 +1,25 @@ +// PR c++/103346 +// { dg-do compile { target c++20 } } + +struct Item {}; + +template<class T, T... ts> +struct Sequence { }; + +template<Item... items> +using ItemSequence = Sequence<Item, items...>; + +template<Item... items> +constexpr auto f() { + constexpr auto l = [](Item item) { return item; }; + return ItemSequence<l(items)...>{}; +} + +using ty0 = decltype(f<>()); +using ty0 = ItemSequence<>; + +using ty1 = decltype(f<{}>()); +using ty1 = ItemSequence<{}>; + +using ty3 = decltype(f<{}, {}, {}>()); +using ty3 = ItemSequence<{}, {}, {}>; diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C new file mode 100644 index 00000000000..8127b1f5426 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C @@ -0,0 +1,23 @@ +// PR c++/104278 +// { dg-do compile { target c++20 } } + +struct foo { + int value; + constexpr foo modify() const { return { value + 1 }; } +}; + +template<foo f, bool Enable = f.value & 1> +struct bar { + static void run() { } +}; + +template<foo f> +struct qux { + static void run() { + bar<f.modify()>::run(); + } +}; + +int main() { + qux<foo{}>::run(); +} diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C new file mode 100644 index 00000000000..afcb3d64495 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C @@ -0,0 +1,15 @@ +// PR c++/102553 +// { dg-do compile { target c++20 } } + +struct s1{}; +template<int> inline constexpr s1 ch{}; + +template<s1 f> struct s2{}; +template<s1 f> using alias1 = s2<f>; + +template<class T> +void general(int n) { + alias1<ch<1>>{}; +} + +template void general<int>(int);
On Tue, 6 Dec 2022, Patrick Palka wrote: > On Tue, 6 Dec 2022, Patrick Palka wrote: > > > This patch fixes some issues with substitution into a C++20 template > > parameter object wrapper: > > > > * The first testcase demonstrates a situation where the same_type_p > > assert in relevant case of tsubst_copy doesn't hold, because (partial) > > substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields > > A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a > > nop and yields A<T> due to tsubst's level == 1 early exit test. So > > this patch just gets rid of the assert; the type mismatch doesn't > > seem to be a problem in practice since the coercion is from one > > dependent type to another. > > > > * In the second testcase, dependent substitution into the underlying > > TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which > > tsubst_copy doesn't expect. This patch fixes this by handling empty > > TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after > > this substitution we're left with a VIEW_CONVERT_EXPR wrapping a > > CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent > > non-dependent substitution tsubst_copy doesn't expect either. So > > this patch also relaxes the tsubst_copy case to accept such > > VIEW_CONVERT_EXPR too. > > > > * In the third testcase, we end up never resolving the call to > > f.modify() since tsubst_copy doesn't do overload resolution. > > This patch fixes this by moving the handling of these > > VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. > > And it turns out (at least according to our testsuite) that > > tsubst_copy doesn't directly need to handle the other kinds of > > NON_LVALUE_EXPR and VIEW_CONVERT_EXPR, so this patch also gets rid > > of the location_wrapper_p handling from tsubst_copy and moves the > > REF_PARENTHESIZED_P handling to tsubst_copy_and_build. > > On second thought, getting rid of the location_wrapper_p and > REF_PARENTHESIZED_P handling from tsubst_copy is perhaps too > risky at this stage. The following patch instead just moves > the tparm object wrapper handling from tsubst_copy to > tsubst_copy_and_build and leaves the rest of tsubst_copy alone. > Smoke tested so far, full bootstrap+regtest in progress: > > -- >8-- > > Subject: [PATCH] c++: NTTP object wrapper substitution fixes [PR103346, ...] > > This patch fixes some issues with substitution into a C++20 template > parameter object wrapper: > > * The first testcase demonstrates a situation where the same_type_p > assert in relevant case of tsubst_copy doesn't hold, because (partial) > substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields > A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a > nop and yields A<T> due to tsubst's level == 1 early exit test. So > this patch just gets rid of the assert; the type mismatch doesn't > seem to be a problem in practice, I suppose because the coercion is > from one dependent type to another. > > * In the second testcase, dependent substitution into the underlying > TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which > tsubst_copy doesn't expect. This patch fixes this by handling empty > TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after > this substitution we're left with a VIEW_CONVERT_EXPR wrapping a > CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent > non-dependent substitution tsubst_copy doesn't expect either. So > this patch also relaxes tsubst_copy to accept such VIEW_CONVERT_EXPR > too. > > * In the third testcase, we end up never resolving the call to > f.modify() since tsubst_copy doesn't do overload resolution. > This patch fixes this by moving the handling of these > VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. > For good measure tsubst_copy_and_build should also handle > REF_PARENTHESIZED_P wrappers instead of delegating to tsubst_copy. > > After this patch, VIEW_CONVERT_EXPR substitution is ultimately just > moved from tsubst_copy to tsubst_copy_and_build and made more > permissive. > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for > trunk? Ping. > > PR c++/103346 > PR c++/104278 > PR c++/102553 > > gcc/cp/ChangeLog: > > * pt.cc (tsubst_copy) <case VIEW_CONVERT_EXPR>: In the handling > of C++20 template parameter object wrappers: Remove same_type_p > assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle > empty TREE_TYPE on substituted inner operand. Move it to ... > (tsubst_copy_and_build): ... here. Also handle REF_PARENTHESIZED_P > VIEW_CONVERT_EXPRs. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp2a/nontype-class52a.C: New test. > * g++.dg/cpp2a/nontype-class53.C: New test. > * g++.dg/cpp2a/nontype-class54.C: New test. > * g++.dg/cpp2a/nontype-class55.C: New test. > --- > gcc/cp/pt.cc | 73 ++++++++++--------- > gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 ++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 ++++ > 5 files changed, 116 insertions(+), 35 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc > index 2d8e4fdd4b5..0a196f069ad 100644 > --- a/gcc/cp/pt.cc > +++ b/gcc/cp/pt.cc > @@ -17271,42 +17271,16 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) > return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); > } > tree op = TREE_OPERAND (t, 0); > - if (code == VIEW_CONVERT_EXPR > - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) > - { > - /* Wrapper to make a C++20 template parameter object const. */ > - op = tsubst_copy (op, args, complain, in_decl); > - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) > - { > - /* The template argument is not const, presumably because > - it is still dependent, and so not the const template parm > - object. */ > - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > - gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p > - (type, TREE_TYPE (op))); > - if (TREE_CODE (op) == CONSTRUCTOR > - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > - { > - /* Don't add a wrapper to these. */ > - op = copy_node (op); > - TREE_TYPE (op) = type; > - } > - else > - /* Do add a wrapper otherwise (in particular, if op is > - another TEMPLATE_PARM_INDEX). */ > - op = build1 (code, type, op); > - } > - return op; > - } > /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > + if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > { > op = tsubst_copy (op, args, complain, in_decl); > op = build1 (code, TREE_TYPE (op), op); > REF_PARENTHESIZED_P (op) = true; > return op; > } > - /* We shouldn't see any other uses of these in templates. */ > + /* We shouldn't see any other uses of these in templates > + (tsubst_copy_and_build handles C++20 tparm object wrappers). */ > gcc_unreachable (); > } > > @@ -21569,12 +21543,41 @@ tsubst_copy_and_build (tree t, > > case NON_LVALUE_EXPR: > case VIEW_CONVERT_EXPR: > - if (location_wrapper_p (t)) > - /* We need to do this here as well as in tsubst_copy so we get the > - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ > - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), > - EXPR_LOCATION (t))); > - /* fallthrough. */ > + { > + tree op = RECUR (TREE_OPERAND (t, 0)); > + if (location_wrapper_p (t)) > + /* We need to do this here as well as in tsubst_copy so we get the > + other tsubst_copy_and_build semantics for a PARM_DECL operand. */ > + RETURN (maybe_wrap_with_location (op, EXPR_LOCATION (t))); > + > + gcc_checking_assert (TREE_CODE (t) == VIEW_CONVERT_EXPR); > + if (REF_PARENTHESIZED_P (t)) > + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > + RETURN (finish_parenthesized_expr (op)); > + > + /* Otherwise, we're dealing with a wrapper to make a C++20 template > + parameter object const. */ > + if (TREE_TYPE (op) == NULL_TREE > + || !CP_TYPE_CONST_P (TREE_TYPE (op))) > + { > + /* The template argument is not const, presumably because > + it is still dependent, and so not the const template parm > + object. */ > + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > + if (TREE_CODE (op) == CONSTRUCTOR > + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > + { > + /* Don't add a wrapper to these. */ > + op = copy_node (op); > + TREE_TYPE (op) = type; > + } > + else > + /* Do add a wrapper otherwise (in particular, if op is > + another TEMPLATE_PARM_INDEX). */ > + op = build1 (VIEW_CONVERT_EXPR, type, op); > + } > + RETURN (op); > + } > > default: > /* Handle Objective-C++ constructs, if appropriate. */ > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > new file mode 100644 > index 00000000000..ae5d5df70ac > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > @@ -0,0 +1,15 @@ > +// A version of nontype-class52.C where explicit template arguments are > +// given in the call to f (which during deduction need to be partially > +// substituted into the NTTP object V in f's signature). > +// { dg-do compile { target c++20 } } > + > +template<class> struct A { }; > + > +template<auto> struct B { }; > + > +template<class T, A<T> V> void f(B<V>); > + > +int main() { > + constexpr A<int> a; > + f<int>(B<a>{}); > +} > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > new file mode 100644 > index 00000000000..9a6398c5f57 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > @@ -0,0 +1,25 @@ > +// PR c++/103346 > +// { dg-do compile { target c++20 } } > + > +struct Item {}; > + > +template<class T, T... ts> > +struct Sequence { }; > + > +template<Item... items> > +using ItemSequence = Sequence<Item, items...>; > + > +template<Item... items> > +constexpr auto f() { > + constexpr auto l = [](Item item) { return item; }; > + return ItemSequence<l(items)...>{}; > +} > + > +using ty0 = decltype(f<>()); > +using ty0 = ItemSequence<>; > + > +using ty1 = decltype(f<{}>()); > +using ty1 = ItemSequence<{}>; > + > +using ty3 = decltype(f<{}, {}, {}>()); > +using ty3 = ItemSequence<{}, {}, {}>; > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > new file mode 100644 > index 00000000000..8127b1f5426 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > @@ -0,0 +1,23 @@ > +// PR c++/104278 > +// { dg-do compile { target c++20 } } > + > +struct foo { > + int value; > + constexpr foo modify() const { return { value + 1 }; } > +}; > + > +template<foo f, bool Enable = f.value & 1> > +struct bar { > + static void run() { } > +}; > + > +template<foo f> > +struct qux { > + static void run() { > + bar<f.modify()>::run(); > + } > +}; > + > +int main() { > + qux<foo{}>::run(); > +} > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > new file mode 100644 > index 00000000000..afcb3d64495 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > @@ -0,0 +1,15 @@ > +// PR c++/102553 > +// { dg-do compile { target c++20 } } > + > +struct s1{}; > +template<int> inline constexpr s1 ch{}; > + > +template<s1 f> struct s2{}; > +template<s1 f> using alias1 = s2<f>; > + > +template<class T> > +void general(int n) { > + alias1<ch<1>>{}; > +} > + > +template void general<int>(int); > -- > 2.39.0.rc2 > >
On 12/6/22 13:35, Patrick Palka wrote: > This patch fixes some issues with substitution into a C++20 template > parameter object wrapper: > > * The first testcase demonstrates a situation where the same_type_p > assert in relevant case of tsubst_copy doesn't hold, because (partial) > substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields > A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a > nop and yields A<T> due to tsubst's level == 1 early exit test. We exit in that case because continuing would reduce the level to an impossible 0. Why doesn't the preceding code find a binding for T? > So > this patch just gets rid of the assert; the type mismatch doesn't > seem to be a problem in practice, I suppose because the coercion is > from one dependent type to another. > > * In the second testcase, dependent substitution into the underlying > TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which > tsubst_copy doesn't expect. This patch fixes this by handling empty > TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after > this substitution we're left with a VIEW_CONVERT_EXPR wrapping a > CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent > non-dependent substitution tsubst_copy doesn't expect either. So > this patch also relaxes tsubst_copy to accept such VIEW_CONVERT_EXPR > too. > > * In the third testcase, we end up never resolving the call to > f.modify() since tsubst_copy doesn't do overload resolution. > This patch fixes this by moving the handling of these > VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. > For good measure tsubst_copy_and_build should also handle > REF_PARENTHESIZED_P wrappers instead of delegating to tsubst_copy. > > After this patch, VIEW_CONVERT_EXPR substitution is ultimately just > moved from tsubst_copy to tsubst_copy_and_build and made more > permissive. > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for > trunk? > > PR c++/103346 > PR c++/104278 > PR c++/102553 > > gcc/cp/ChangeLog: > > * pt.cc (tsubst_copy) <case VIEW_CONVERT_EXPR>: In the handling > of C++20 template parameter object wrappers: Remove same_type_p > assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle > empty TREE_TYPE on substituted inner operand. Move it to ... > (tsubst_copy_and_build): ... here. Also handle REF_PARENTHESIZED_P > VIEW_CONVERT_EXPRs. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp2a/nontype-class52a.C: New test. > * g++.dg/cpp2a/nontype-class53.C: New test. > * g++.dg/cpp2a/nontype-class54.C: New test. > * g++.dg/cpp2a/nontype-class55.C: New test. > --- > gcc/cp/pt.cc | 73 ++++++++++--------- > gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 ++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++++ > gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 ++++ > 5 files changed, 116 insertions(+), 35 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc > index 2d8e4fdd4b5..0a196f069ad 100644 > --- a/gcc/cp/pt.cc > +++ b/gcc/cp/pt.cc > @@ -17271,42 +17271,16 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) > return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); > } > tree op = TREE_OPERAND (t, 0); > - if (code == VIEW_CONVERT_EXPR > - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) > - { > - /* Wrapper to make a C++20 template parameter object const. */ > - op = tsubst_copy (op, args, complain, in_decl); > - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) > - { > - /* The template argument is not const, presumably because > - it is still dependent, and so not the const template parm > - object. */ > - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > - gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p > - (type, TREE_TYPE (op))); > - if (TREE_CODE (op) == CONSTRUCTOR > - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > - { > - /* Don't add a wrapper to these. */ > - op = copy_node (op); > - TREE_TYPE (op) = type; > - } > - else > - /* Do add a wrapper otherwise (in particular, if op is > - another TEMPLATE_PARM_INDEX). */ > - op = build1 (code, type, op); > - } > - return op; > - } > /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > + if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > { > op = tsubst_copy (op, args, complain, in_decl); > op = build1 (code, TREE_TYPE (op), op); > REF_PARENTHESIZED_P (op) = true; > return op; > } > - /* We shouldn't see any other uses of these in templates. */ > + /* We shouldn't see any other uses of these in templates > + (tsubst_copy_and_build handles C++20 tparm object wrappers). */ > gcc_unreachable (); > } > > @@ -21569,12 +21543,41 @@ tsubst_copy_and_build (tree t, > > case NON_LVALUE_EXPR: > case VIEW_CONVERT_EXPR: > - if (location_wrapper_p (t)) > - /* We need to do this here as well as in tsubst_copy so we get the > - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ > - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), > - EXPR_LOCATION (t))); > - /* fallthrough. */ > + { > + tree op = RECUR (TREE_OPERAND (t, 0)); > + if (location_wrapper_p (t)) > + /* We need to do this here as well as in tsubst_copy so we get the > + other tsubst_copy_and_build semantics for a PARM_DECL operand. */ > + RETURN (maybe_wrap_with_location (op, EXPR_LOCATION (t))); > + > + gcc_checking_assert (TREE_CODE (t) == VIEW_CONVERT_EXPR); > + if (REF_PARENTHESIZED_P (t)) > + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > + RETURN (finish_parenthesized_expr (op)); > + > + /* Otherwise, we're dealing with a wrapper to make a C++20 template > + parameter object const. */ > + if (TREE_TYPE (op) == NULL_TREE > + || !CP_TYPE_CONST_P (TREE_TYPE (op))) > + { > + /* The template argument is not const, presumably because > + it is still dependent, and so not the const template parm > + object. */ > + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > + if (TREE_CODE (op) == CONSTRUCTOR > + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > + { > + /* Don't add a wrapper to these. */ > + op = copy_node (op); > + TREE_TYPE (op) = type; > + } > + else > + /* Do add a wrapper otherwise (in particular, if op is > + another TEMPLATE_PARM_INDEX). */ > + op = build1 (VIEW_CONVERT_EXPR, type, op); > + } > + RETURN (op); > + } > > default: > /* Handle Objective-C++ constructs, if appropriate. */ > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > new file mode 100644 > index 00000000000..ae5d5df70ac > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > @@ -0,0 +1,15 @@ > +// A version of nontype-class52.C where explicit template arguments are > +// given in the call to f (which during deduction need to be partially > +// substituted into the NTTP object V in f's signature). > +// { dg-do compile { target c++20 } } > + > +template<class> struct A { }; > + > +template<auto> struct B { }; > + > +template<class T, A<T> V> void f(B<V>); > + > +int main() { > + constexpr A<int> a; > + f<int>(B<a>{}); > +} > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > new file mode 100644 > index 00000000000..9a6398c5f57 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > @@ -0,0 +1,25 @@ > +// PR c++/103346 > +// { dg-do compile { target c++20 } } > + > +struct Item {}; > + > +template<class T, T... ts> > +struct Sequence { }; > + > +template<Item... items> > +using ItemSequence = Sequence<Item, items...>; > + > +template<Item... items> > +constexpr auto f() { > + constexpr auto l = [](Item item) { return item; }; > + return ItemSequence<l(items)...>{}; > +} > + > +using ty0 = decltype(f<>()); > +using ty0 = ItemSequence<>; > + > +using ty1 = decltype(f<{}>()); > +using ty1 = ItemSequence<{}>; > + > +using ty3 = decltype(f<{}, {}, {}>()); > +using ty3 = ItemSequence<{}, {}, {}>; > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > new file mode 100644 > index 00000000000..8127b1f5426 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > @@ -0,0 +1,23 @@ > +// PR c++/104278 > +// { dg-do compile { target c++20 } } > + > +struct foo { > + int value; > + constexpr foo modify() const { return { value + 1 }; } > +}; > + > +template<foo f, bool Enable = f.value & 1> > +struct bar { > + static void run() { } > +}; > + > +template<foo f> > +struct qux { > + static void run() { > + bar<f.modify()>::run(); > + } > +}; > + > +int main() { > + qux<foo{}>::run(); > +} > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > new file mode 100644 > index 00000000000..afcb3d64495 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > @@ -0,0 +1,15 @@ > +// PR c++/102553 > +// { dg-do compile { target c++20 } } > + > +struct s1{}; > +template<int> inline constexpr s1 ch{}; > + > +template<s1 f> struct s2{}; > +template<s1 f> using alias1 = s2<f>; > + > +template<class T> > +void general(int n) { > + alias1<ch<1>>{}; > +} > + > +template void general<int>(int);
On Mon, 19 Dec 2022, Jason Merrill wrote: > On 12/6/22 13:35, Patrick Palka wrote: > > This patch fixes some issues with substitution into a C++20 template > > parameter object wrapper: > > > > * The first testcase demonstrates a situation where the same_type_p > > assert in relevant case of tsubst_copy doesn't hold, because (partial) > > substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields > > A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a > > nop and yields A<T> due to tsubst's level == 1 early exit test. > > We exit in that case because continuing would reduce the level to an > impossible 0. Why doesn't the preceding code find a binding for T? Whoops, I misspoke. The problem is that there's no binding for V since only T=int was explicitly specified, so when substituting into the TEMPLATE_PARM_INDEX for V in 'void f(B<V>)', we hit that early exit and never get a chance to substitute T=int into the tpi's TREE_TYPE (which would yield A<int> as desired). So the TREE_TYPE of the wrapped tpi remains A<T> whereas the substituted TREE_TYPE of the wrapper is A<int>, a mismatch. > > > So > > this patch just gets rid of the assert; the type mismatch doesn't > > seem to be a problem in practice, I suppose because the coercion is > > from one dependent type to another. > > > > * In the second testcase, dependent substitution into the underlying > > TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which > > tsubst_copy doesn't expect. This patch fixes this by handling empty > > TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after > > this substitution we're left with a VIEW_CONVERT_EXPR wrapping a > > CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent > > non-dependent substitution tsubst_copy doesn't expect either. So > > this patch also relaxes tsubst_copy to accept such VIEW_CONVERT_EXPR > > too. > > > > * In the third testcase, we end up never resolving the call to > > f.modify() since tsubst_copy doesn't do overload resolution. > > This patch fixes this by moving the handling of these > > VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. > > For good measure tsubst_copy_and_build should also handle > > REF_PARENTHESIZED_P wrappers instead of delegating to tsubst_copy. > > > > After this patch, VIEW_CONVERT_EXPR substitution is ultimately just > > moved from tsubst_copy to tsubst_copy_and_build and made more > > permissive. > > > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for > > trunk? > > > > PR c++/103346 > > PR c++/104278 > > PR c++/102553 > > > > gcc/cp/ChangeLog: > > > > * pt.cc (tsubst_copy) <case VIEW_CONVERT_EXPR>: In the handling > > of C++20 template parameter object wrappers: Remove same_type_p > > assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle > > empty TREE_TYPE on substituted inner operand. Move it to ... > > (tsubst_copy_and_build): ... here. Also handle REF_PARENTHESIZED_P > > VIEW_CONVERT_EXPRs. > > > > gcc/testsuite/ChangeLog: > > > > * g++.dg/cpp2a/nontype-class52a.C: New test. > > * g++.dg/cpp2a/nontype-class53.C: New test. > > * g++.dg/cpp2a/nontype-class54.C: New test. > > * g++.dg/cpp2a/nontype-class55.C: New test. > > --- > > gcc/cp/pt.cc | 73 ++++++++++--------- > > gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 ++++ > > gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++++ > > gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++++ > > gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 ++++ > > 5 files changed, 116 insertions(+), 35 deletions(-) > > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > > create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc > > index 2d8e4fdd4b5..0a196f069ad 100644 > > --- a/gcc/cp/pt.cc > > +++ b/gcc/cp/pt.cc > > @@ -17271,42 +17271,16 @@ tsubst_copy (tree t, tree args, tsubst_flags_t > > complain, tree in_decl) > > return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); > > } > > tree op = TREE_OPERAND (t, 0); > > - if (code == VIEW_CONVERT_EXPR > > - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) > > - { > > - /* Wrapper to make a C++20 template parameter object const. */ > > - op = tsubst_copy (op, args, complain, in_decl); > > - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) > > - { > > - /* The template argument is not const, presumably because > > - it is still dependent, and so not the const template parm > > - object. */ > > - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > > - gcc_checking_assert > > (same_type_ignoring_top_level_qualifiers_p > > - (type, TREE_TYPE (op))); > > - if (TREE_CODE (op) == CONSTRUCTOR > > - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > > - { > > - /* Don't add a wrapper to these. */ > > - op = copy_node (op); > > - TREE_TYPE (op) = type; > > - } > > - else > > - /* Do add a wrapper otherwise (in particular, if op is > > - another TEMPLATE_PARM_INDEX). */ > > - op = build1 (code, type, op); > > - } > > - return op; > > - } > > /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > > - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > > + if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) > > { > > op = tsubst_copy (op, args, complain, in_decl); > > op = build1 (code, TREE_TYPE (op), op); > > REF_PARENTHESIZED_P (op) = true; > > return op; > > } > > - /* We shouldn't see any other uses of these in templates. */ > > + /* We shouldn't see any other uses of these in templates > > + (tsubst_copy_and_build handles C++20 tparm object wrappers). */ > > gcc_unreachable (); > > } > > @@ -21569,12 +21543,41 @@ tsubst_copy_and_build (tree t, > > case NON_LVALUE_EXPR: > > case VIEW_CONVERT_EXPR: > > - if (location_wrapper_p (t)) > > - /* We need to do this here as well as in tsubst_copy so we get the > > - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ > > - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), > > - EXPR_LOCATION (t))); > > - /* fallthrough. */ > > + { > > + tree op = RECUR (TREE_OPERAND (t, 0)); > > + if (location_wrapper_p (t)) > > + /* We need to do this here as well as in tsubst_copy so we get the > > + other tsubst_copy_and_build semantics for a PARM_DECL operand. > > */ > > + RETURN (maybe_wrap_with_location (op, EXPR_LOCATION (t))); > > + > > + gcc_checking_assert (TREE_CODE (t) == VIEW_CONVERT_EXPR); > > + if (REF_PARENTHESIZED_P (t)) > > + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ > > + RETURN (finish_parenthesized_expr (op)); > > + > > + /* Otherwise, we're dealing with a wrapper to make a C++20 template > > + parameter object const. */ > > + if (TREE_TYPE (op) == NULL_TREE > > + || !CP_TYPE_CONST_P (TREE_TYPE (op))) > > + { > > + /* The template argument is not const, presumably because > > + it is still dependent, and so not the const template parm > > + object. */ > > + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); > > + if (TREE_CODE (op) == CONSTRUCTOR > > + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) > > + { > > + /* Don't add a wrapper to these. */ > > + op = copy_node (op); > > + TREE_TYPE (op) = type; > > + } > > + else > > + /* Do add a wrapper otherwise (in particular, if op is > > + another TEMPLATE_PARM_INDEX). */ > > + op = build1 (VIEW_CONVERT_EXPR, type, op); > > + } > > + RETURN (op); > > + } > > default: > > /* Handle Objective-C++ constructs, if appropriate. */ > > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > > b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > > new file mode 100644 > > index 00000000000..ae5d5df70ac > > --- /dev/null > > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C > > @@ -0,0 +1,15 @@ > > +// A version of nontype-class52.C where explicit template arguments are > > +// given in the call to f (which during deduction need to be partially > > +// substituted into the NTTP object V in f's signature). > > +// { dg-do compile { target c++20 } } > > + > > +template<class> struct A { }; > > + > > +template<auto> struct B { }; > > + > > +template<class T, A<T> V> void f(B<V>); > > + > > +int main() { > > + constexpr A<int> a; > > + f<int>(B<a>{}); > > +} > > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > > b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > > new file mode 100644 > > index 00000000000..9a6398c5f57 > > --- /dev/null > > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C > > @@ -0,0 +1,25 @@ > > +// PR c++/103346 > > +// { dg-do compile { target c++20 } } > > + > > +struct Item {}; > > + > > +template<class T, T... ts> > > +struct Sequence { }; > > + > > +template<Item... items> > > +using ItemSequence = Sequence<Item, items...>; > > + > > +template<Item... items> > > +constexpr auto f() { > > + constexpr auto l = [](Item item) { return item; }; > > + return ItemSequence<l(items)...>{}; > > +} > > + > > +using ty0 = decltype(f<>()); > > +using ty0 = ItemSequence<>; > > + > > +using ty1 = decltype(f<{}>()); > > +using ty1 = ItemSequence<{}>; > > + > > +using ty3 = decltype(f<{}, {}, {}>()); > > +using ty3 = ItemSequence<{}, {}, {}>; > > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > > b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > > new file mode 100644 > > index 00000000000..8127b1f5426 > > --- /dev/null > > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C > > @@ -0,0 +1,23 @@ > > +// PR c++/104278 > > +// { dg-do compile { target c++20 } } > > + > > +struct foo { > > + int value; > > + constexpr foo modify() const { return { value + 1 }; } > > +}; > > + > > +template<foo f, bool Enable = f.value & 1> > > +struct bar { > > + static void run() { } > > +}; > > + > > +template<foo f> > > +struct qux { > > + static void run() { > > + bar<f.modify()>::run(); > > + } > > +}; > > + > > +int main() { > > + qux<foo{}>::run(); > > +} > > diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > new file mode 100644 > > index 00000000000..afcb3d64495 > > --- /dev/null > > +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C > > @@ -0,0 +1,15 @@ > > +// PR c++/102553 > > +// { dg-do compile { target c++20 } } > > + > > +struct s1{}; > > +template<int> inline constexpr s1 ch{}; > > + > > +template<s1 f> struct s2{}; > > +template<s1 f> using alias1 = s2<f>; > > + > > +template<class T> > > +void general(int n) { > > + alias1<ch<1>>{}; > > +} > > + > > +template void general<int>(int); > >
On 12/19/22 13:13, Patrick Palka wrote: > On Mon, 19 Dec 2022, Jason Merrill wrote: > >> On 12/6/22 13:35, Patrick Palka wrote: >>> This patch fixes some issues with substitution into a C++20 template >>> parameter object wrapper: >>> >>> * The first testcase demonstrates a situation where the same_type_p >>> assert in relevant case of tsubst_copy doesn't hold, because (partial) >>> substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields >>> A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a >>> nop and yields A<T> due to tsubst's level == 1 early exit test. >> >> We exit in that case because continuing would reduce the level to an >> impossible 0. Why doesn't the preceding code find a binding for T? > > Whoops, I misspoke. The problem is that there's no binding for V since > only T=int was explicitly specified, so when substituting into the > TEMPLATE_PARM_INDEX for V in 'void f(B<V>)', we hit that early exit and > never get a chance to substitute T=int into the tpi's TREE_TYPE (which > would yield A<int> as desired). So the TREE_TYPE of the wrapped tpi > remains A<T> whereas the substituted TREE_TYPE of the wrapper is A<int>, > a mismatch. Ah, makes sense. The patch is OK. >> >>> So >>> this patch just gets rid of the assert; the type mismatch doesn't >>> seem to be a problem in practice, I suppose because the coercion is >>> from one dependent type to another. >>> >>> * In the second testcase, dependent substitution into the underlying >>> TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which >>> tsubst_copy doesn't expect. This patch fixes this by handling empty >>> TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after >>> this substitution we're left with a VIEW_CONVERT_EXPR wrapping a >>> CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent >>> non-dependent substitution tsubst_copy doesn't expect either. So >>> this patch also relaxes tsubst_copy to accept such VIEW_CONVERT_EXPR >>> too. >>> >>> * In the third testcase, we end up never resolving the call to >>> f.modify() since tsubst_copy doesn't do overload resolution. >>> This patch fixes this by moving the handling of these >>> VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. >>> For good measure tsubst_copy_and_build should also handle >>> REF_PARENTHESIZED_P wrappers instead of delegating to tsubst_copy. >>> >>> After this patch, VIEW_CONVERT_EXPR substitution is ultimately just >>> moved from tsubst_copy to tsubst_copy_and_build and made more >>> permissive. >>> >>> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for >>> trunk? >>> >>> PR c++/103346 >>> PR c++/104278 >>> PR c++/102553 >>> >>> gcc/cp/ChangeLog: >>> >>> * pt.cc (tsubst_copy) <case VIEW_CONVERT_EXPR>: In the handling >>> of C++20 template parameter object wrappers: Remove same_type_p >>> assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle >>> empty TREE_TYPE on substituted inner operand. Move it to ... >>> (tsubst_copy_and_build): ... here. Also handle REF_PARENTHESIZED_P >>> VIEW_CONVERT_EXPRs. >>> >>> gcc/testsuite/ChangeLog: >>> >>> * g++.dg/cpp2a/nontype-class52a.C: New test. >>> * g++.dg/cpp2a/nontype-class53.C: New test. >>> * g++.dg/cpp2a/nontype-class54.C: New test. >>> * g++.dg/cpp2a/nontype-class55.C: New test. >>> --- >>> gcc/cp/pt.cc | 73 ++++++++++--------- >>> gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 ++++ >>> gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++++ >>> gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++++ >>> gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 ++++ >>> 5 files changed, 116 insertions(+), 35 deletions(-) >>> create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C >>> create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C >>> create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C >>> create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C >>> >>> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc >>> index 2d8e4fdd4b5..0a196f069ad 100644 >>> --- a/gcc/cp/pt.cc >>> +++ b/gcc/cp/pt.cc >>> @@ -17271,42 +17271,16 @@ tsubst_copy (tree t, tree args, tsubst_flags_t >>> complain, tree in_decl) >>> return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); >>> } >>> tree op = TREE_OPERAND (t, 0); >>> - if (code == VIEW_CONVERT_EXPR >>> - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) >>> - { >>> - /* Wrapper to make a C++20 template parameter object const. */ >>> - op = tsubst_copy (op, args, complain, in_decl); >>> - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) >>> - { >>> - /* The template argument is not const, presumably because >>> - it is still dependent, and so not the const template parm >>> - object. */ >>> - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); >>> - gcc_checking_assert >>> (same_type_ignoring_top_level_qualifiers_p >>> - (type, TREE_TYPE (op))); >>> - if (TREE_CODE (op) == CONSTRUCTOR >>> - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) >>> - { >>> - /* Don't add a wrapper to these. */ >>> - op = copy_node (op); >>> - TREE_TYPE (op) = type; >>> - } >>> - else >>> - /* Do add a wrapper otherwise (in particular, if op is >>> - another TEMPLATE_PARM_INDEX). */ >>> - op = build1 (code, type, op); >>> - } >>> - return op; >>> - } >>> /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ >>> - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) >>> + if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) >>> { >>> op = tsubst_copy (op, args, complain, in_decl); >>> op = build1 (code, TREE_TYPE (op), op); >>> REF_PARENTHESIZED_P (op) = true; >>> return op; >>> } >>> - /* We shouldn't see any other uses of these in templates. */ >>> + /* We shouldn't see any other uses of these in templates >>> + (tsubst_copy_and_build handles C++20 tparm object wrappers). */ >>> gcc_unreachable (); >>> } >>> @@ -21569,12 +21543,41 @@ tsubst_copy_and_build (tree t, >>> case NON_LVALUE_EXPR: >>> case VIEW_CONVERT_EXPR: >>> - if (location_wrapper_p (t)) >>> - /* We need to do this here as well as in tsubst_copy so we get the >>> - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ >>> - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), >>> - EXPR_LOCATION (t))); >>> - /* fallthrough. */ >>> + { >>> + tree op = RECUR (TREE_OPERAND (t, 0)); >>> + if (location_wrapper_p (t)) >>> + /* We need to do this here as well as in tsubst_copy so we get the >>> + other tsubst_copy_and_build semantics for a PARM_DECL operand. >>> */ >>> + RETURN (maybe_wrap_with_location (op, EXPR_LOCATION (t))); >>> + >>> + gcc_checking_assert (TREE_CODE (t) == VIEW_CONVERT_EXPR); >>> + if (REF_PARENTHESIZED_P (t)) >>> + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ >>> + RETURN (finish_parenthesized_expr (op)); >>> + >>> + /* Otherwise, we're dealing with a wrapper to make a C++20 template >>> + parameter object const. */ >>> + if (TREE_TYPE (op) == NULL_TREE >>> + || !CP_TYPE_CONST_P (TREE_TYPE (op))) >>> + { >>> + /* The template argument is not const, presumably because >>> + it is still dependent, and so not the const template parm >>> + object. */ >>> + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); >>> + if (TREE_CODE (op) == CONSTRUCTOR >>> + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) >>> + { >>> + /* Don't add a wrapper to these. */ >>> + op = copy_node (op); >>> + TREE_TYPE (op) = type; >>> + } >>> + else >>> + /* Do add a wrapper otherwise (in particular, if op is >>> + another TEMPLATE_PARM_INDEX). */ >>> + op = build1 (VIEW_CONVERT_EXPR, type, op); >>> + } >>> + RETURN (op); >>> + } >>> default: >>> /* Handle Objective-C++ constructs, if appropriate. */ >>> diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C >>> b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C >>> new file mode 100644 >>> index 00000000000..ae5d5df70ac >>> --- /dev/null >>> +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C >>> @@ -0,0 +1,15 @@ >>> +// A version of nontype-class52.C where explicit template arguments are >>> +// given in the call to f (which during deduction need to be partially >>> +// substituted into the NTTP object V in f's signature). >>> +// { dg-do compile { target c++20 } } >>> + >>> +template<class> struct A { }; >>> + >>> +template<auto> struct B { }; >>> + >>> +template<class T, A<T> V> void f(B<V>); >>> + >>> +int main() { >>> + constexpr A<int> a; >>> + f<int>(B<a>{}); >>> +} >>> diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C >>> b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C >>> new file mode 100644 >>> index 00000000000..9a6398c5f57 >>> --- /dev/null >>> +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C >>> @@ -0,0 +1,25 @@ >>> +// PR c++/103346 >>> +// { dg-do compile { target c++20 } } >>> + >>> +struct Item {}; >>> + >>> +template<class T, T... ts> >>> +struct Sequence { }; >>> + >>> +template<Item... items> >>> +using ItemSequence = Sequence<Item, items...>; >>> + >>> +template<Item... items> >>> +constexpr auto f() { >>> + constexpr auto l = [](Item item) { return item; }; >>> + return ItemSequence<l(items)...>{}; >>> +} >>> + >>> +using ty0 = decltype(f<>()); >>> +using ty0 = ItemSequence<>; >>> + >>> +using ty1 = decltype(f<{}>()); >>> +using ty1 = ItemSequence<{}>; >>> + >>> +using ty3 = decltype(f<{}, {}, {}>()); >>> +using ty3 = ItemSequence<{}, {}, {}>; >>> diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C >>> b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C >>> new file mode 100644 >>> index 00000000000..8127b1f5426 >>> --- /dev/null >>> +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C >>> @@ -0,0 +1,23 @@ >>> +// PR c++/104278 >>> +// { dg-do compile { target c++20 } } >>> + >>> +struct foo { >>> + int value; >>> + constexpr foo modify() const { return { value + 1 }; } >>> +}; >>> + >>> +template<foo f, bool Enable = f.value & 1> >>> +struct bar { >>> + static void run() { } >>> +}; >>> + >>> +template<foo f> >>> +struct qux { >>> + static void run() { >>> + bar<f.modify()>::run(); >>> + } >>> +}; >>> + >>> +int main() { >>> + qux<foo{}>::run(); >>> +} >>> diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C >>> b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C >>> new file mode 100644 >>> index 00000000000..afcb3d64495 >>> --- /dev/null >>> +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C >>> @@ -0,0 +1,15 @@ >>> +// PR c++/102553 >>> +// { dg-do compile { target c++20 } } >>> + >>> +struct s1{}; >>> +template<int> inline constexpr s1 ch{}; >>> + >>> +template<s1 f> struct s2{}; >>> +template<s1 f> using alias1 = s2<f>; >>> + >>> +template<class T> >>> +void general(int n) { >>> + alias1<ch<1>>{}; >>> +} >>> + >>> +template void general<int>(int); >> >> >
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index 2d8e4fdd4b5..021c2be9257 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -17257,59 +17257,6 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) /* Ordinary template template argument. */ return t; - case NON_LVALUE_EXPR: - case VIEW_CONVERT_EXPR: - { - /* Handle location wrappers by substituting the wrapped node - first, *then* reusing the resulting type. Doing the type - first ensures that we handle template parameters and - parameter pack expansions. */ - if (location_wrapper_p (t)) - { - tree op0 = tsubst_copy (TREE_OPERAND (t, 0), args, - complain, in_decl); - return maybe_wrap_with_location (op0, EXPR_LOCATION (t)); - } - tree op = TREE_OPERAND (t, 0); - if (code == VIEW_CONVERT_EXPR - && TREE_CODE (op) == TEMPLATE_PARM_INDEX) - { - /* Wrapper to make a C++20 template parameter object const. */ - op = tsubst_copy (op, args, complain, in_decl); - if (!CP_TYPE_CONST_P (TREE_TYPE (op))) - { - /* The template argument is not const, presumably because - it is still dependent, and so not the const template parm - object. */ - tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); - gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p - (type, TREE_TYPE (op))); - if (TREE_CODE (op) == CONSTRUCTOR - || TREE_CODE (op) == IMPLICIT_CONV_EXPR) - { - /* Don't add a wrapper to these. */ - op = copy_node (op); - TREE_TYPE (op) = type; - } - else - /* Do add a wrapper otherwise (in particular, if op is - another TEMPLATE_PARM_INDEX). */ - op = build1 (code, type, op); - } - return op; - } - /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ - else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t)) - { - op = tsubst_copy (op, args, complain, in_decl); - op = build1 (code, TREE_TYPE (op), op); - REF_PARENTHESIZED_P (op) = true; - return op; - } - /* We shouldn't see any other uses of these in templates. */ - gcc_unreachable (); - } - case CAST_EXPR: case REINTERPRET_CAST_EXPR: case CONST_CAST_EXPR: @@ -21568,13 +21515,48 @@ tsubst_copy_and_build (tree t, RETURN (t); case NON_LVALUE_EXPR: + gcc_checking_assert (location_wrapper_p (t)); + RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), + EXPR_LOCATION (t))); + case VIEW_CONVERT_EXPR: - if (location_wrapper_p (t)) - /* We need to do this here as well as in tsubst_copy so we get the - other tsubst_copy_and_build semantics for a PARM_DECL operand. */ - RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), - EXPR_LOCATION (t))); - /* fallthrough. */ + { + if (location_wrapper_p (t)) + RETURN (maybe_wrap_with_location (RECUR (TREE_OPERAND (t, 0)), + EXPR_LOCATION (t))); + tree op = TREE_OPERAND (t, 0); + if (REF_PARENTHESIZED_P (t)) + { + /* force_paren_expr can also create a VIEW_CONVERT_EXPR. */ + op = RECUR (op); + op = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (op), op); + REF_PARENTHESIZED_P (op) = true; + RETURN (op); + } + /* We're dealing with a wrapper to make a C++20 template parameter + object const. */ + op = RECUR (op); + if (TREE_TYPE (op) == NULL_TREE + || !CP_TYPE_CONST_P (TREE_TYPE (op))) + { + /* The template argument is not const, presumably because + it is still dependent, and so not the const template parm + object. */ + tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); + if (TREE_CODE (op) == CONSTRUCTOR + || TREE_CODE (op) == IMPLICIT_CONV_EXPR) + { + /* Don't add a wrapper to these. */ + op = copy_node (op); + TREE_TYPE (op) = type; + } + else + /* Do add a wrapper otherwise (in particular, if op is + another TEMPLATE_PARM_INDEX). */ + op = build1 (VIEW_CONVERT_EXPR, type, op); + } + RETURN (op); + } default: /* Handle Objective-C++ constructs, if appropriate. */ diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C new file mode 100644 index 00000000000..ae5d5df70ac --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C @@ -0,0 +1,15 @@ +// A version of nontype-class52.C where explicit template arguments are +// given in the call to f (which during deduction need to be partially +// substituted into the NTTP object V in f's signature). +// { dg-do compile { target c++20 } } + +template<class> struct A { }; + +template<auto> struct B { }; + +template<class T, A<T> V> void f(B<V>); + +int main() { + constexpr A<int> a; + f<int>(B<a>{}); +} diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C new file mode 100644 index 00000000000..9a6398c5f57 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class53.C @@ -0,0 +1,25 @@ +// PR c++/103346 +// { dg-do compile { target c++20 } } + +struct Item {}; + +template<class T, T... ts> +struct Sequence { }; + +template<Item... items> +using ItemSequence = Sequence<Item, items...>; + +template<Item... items> +constexpr auto f() { + constexpr auto l = [](Item item) { return item; }; + return ItemSequence<l(items)...>{}; +} + +using ty0 = decltype(f<>()); +using ty0 = ItemSequence<>; + +using ty1 = decltype(f<{}>()); +using ty1 = ItemSequence<{}>; + +using ty3 = decltype(f<{}, {}, {}>()); +using ty3 = ItemSequence<{}, {}, {}>; diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C new file mode 100644 index 00000000000..8127b1f5426 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class54.C @@ -0,0 +1,23 @@ +// PR c++/104278 +// { dg-do compile { target c++20 } } + +struct foo { + int value; + constexpr foo modify() const { return { value + 1 }; } +}; + +template<foo f, bool Enable = f.value & 1> +struct bar { + static void run() { } +}; + +template<foo f> +struct qux { + static void run() { + bar<f.modify()>::run(); + } +}; + +int main() { + qux<foo{}>::run(); +} diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C new file mode 100644 index 00000000000..afcb3d64495 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class55.C @@ -0,0 +1,15 @@ +// PR c++/102553 +// { dg-do compile { target c++20 } } + +struct s1{}; +template<int> inline constexpr s1 ch{}; + +template<s1 f> struct s2{}; +template<s1 f> using alias1 = s2<f>; + +template<class T> +void general(int n) { + alias1<ch<1>>{}; +} + +template void general<int>(int);
This patch fixes some issues with substitution into a C++20 template parameter object wrapper: * The first testcase demonstrates a situation where the same_type_p assert in relevant case of tsubst_copy doesn't hold, because (partial) substitution of {int,} into the VIEW_CONVERT_EXPR wrapper yields A<int> but substitution into the underlying TEMPLATE_PARM_INDEX is a nop and yields A<T> due to tsubst's level == 1 early exit test. So this patch just gets rid of the assert; the type mismatch doesn't seem to be a problem in practice since the coercion is from one dependent type to another. * In the second testcase, dependent substitution into the underlying TEMPLATE_PARM_INDEX yields a CALL_EXPR with empty TREE_TYPE, which tsubst_copy doesn't expect. This patch fixes this by handling empty TREE_TYPE the same way as a non-const TREE_TYPE. Moreover, after this substitution we're left with a VIEW_CONVERT_EXPR wrapping a CALL_EXPR instead of a TEMPLATE_PARM_INDEX, which during the subsequent non-dependent substitution tsubst_copy doesn't expect either. So this patch also relaxes the tsubst_copy case to accept such VIEW_CONVERT_EXPR too. * In the third testcase, we end up never resolving the call to f.modify() since tsubst_copy doesn't do overload resolution. This patch fixes this by moving the handling of these VIEW_CONVERT_EXPR wrappers from tsubst_copy to tsubst_copy_and_build. And it turns out (at least according to our testsuite) that tsubst_copy doesn't directly need to handle the other kinds of NON_LVALUE_EXPR and VIEW_CONVERT_EXPR, so this patch also gets rid of the location_wrapper_p handling from tsubst_copy and moves the REF_PARENTHESIZED_P handling to tsubst_copy_and_build. After this patch, VIEW_CONVERT_EXPR substitution is ultimately just moved from tsubst_copy to tsubst_copy_and_build and made more permissive. Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for trunk? PR c++/103346 PR c++/104278 PR c++/102553 gcc/cp/ChangeLog: * pt.cc (tsubst_copy) <case NON_LVALUE_EXPR, VIEW_CONVERT_EXPR>: Remove same_type_p assert. Accept non-TEMPLATE_PARM_INDEX inner operand. Handle empty TREE_TYPE on substituted inner operand. Move all of this handling to ... (tsubst_copy_and_build): ... here and simplify accordingly. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/nontype-class52a.C: New test. * g++.dg/cpp2a/nontype-class53.C: New test. * g++.dg/cpp2a/nontype-class54.C: New test. * g++.dg/cpp2a/nontype-class55.C: New test. --- gcc/cp/pt.cc | 100 +++++++----------- gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C | 15 +++ gcc/testsuite/g++.dg/cpp2a/nontype-class53.C | 25 +++++ gcc/testsuite/g++.dg/cpp2a/nontype-class54.C | 23 ++++ gcc/testsuite/g++.dg/cpp2a/nontype-class55.C | 15 +++ 5 files changed, 119 insertions(+), 59 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class52a.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class53.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class54.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class55.C