On Thu, Mar 21, 2024 at 05:27:37PM -0400, Jason Merrill wrote:
> On 3/21/24 17:01, Marek Polacek wrote:
> > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
> >
> > -- >8 --
> > Patrick noticed that my r14-9339-gdc6c3bfb59baab patch is wrong;
> > we're dealing with a noexcept-spec there, not a noexcept-expr, so
> > setting cp_noexcept_operand et al is incorrect. Back to the drawing
> > board then.
> >
> > To fix noexcept84.C, we should probably avoid doing push_to_top_level
> > in certain cases. Patrick suggested checking:
> >
> > const bool push_to_top = current_function_decl != fn;
> >
> > which works, but I'm not sure I follow the logic there. I also came
> > up with
> >
> > const bool push_to_top = !decl_function_context (fn);
> >
> > which also works. But ultimately I went with !DECL_TEMPLATE_INSTANTIATED;
> > if DECL_TEMPLATE_INSTANTIATED is set, we've already pushed to top level
> > if it was necessary in instantiate_body.
>
> This sort of thing is what maybe_push_to_top_level is for, does that also
> work?
Sadly -- and I should have mentioned that -- no. maybe_push_to_top_level asks:
bool push_to_top
= !(current_function_decl
&& !LAMBDA_FUNCTION_P (d)
&& decl_function_context (d) == current_function_decl);
here both d and current_function_decl are test()::S::S(), and
decl_function_context (d) is test(). (current_function_decl was
set to test()::S::S() by an earlier push_access_scope call.)
But I want it to work, and I think using maybe_ would be a way nicer
fix. So what if we don't push to top level if decl_function_context
is non-null? I had to add the LAMBDA_TYPE_P check though: it looks
that we always have to push to top level for lambdas, but sometimes
we get a lambda's TYPE_DECL, and LAMBDA_FUNCTION_P doesn't catch
that. An example is lambda-nested4.C.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
-- >8 --
Patrick noticed that my r14-9339-gdc6c3bfb59baab patch is wrong;
we're dealing with a noexcept-spec there, not a noexcept-expr, so
setting cp_noexcept_operand et al is incorrect. Back to the drawing
board then.
To fix noexcept84.C, we should probably avoid doing push_to_top_level
in certain cases. maybe_push_to_top_level didn't work here as-is, so
I changed it to not push to top level if decl_function_context is
non-null, when we are not dealing with a lambda.
This also fixes c++/114349, introduced by r14-9339.
PR c++/114349
gcc/cp/ChangeLog:
* name-lookup.cc (maybe_push_to_top_level): For a non-lambda,
don't push to top level if decl_function_context is non-null.
* pt.cc (maybe_instantiate_noexcept): Use maybe_push_to_top_level.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/noexcept85.C: New test.
* g++.dg/cpp0x/noexcept86.C: New test.
---
gcc/cp/name-lookup.cc | 12 ++++++---
gcc/cp/pt.cc | 11 ++-------
gcc/testsuite/g++.dg/cpp0x/noexcept85.C | 33 +++++++++++++++++++++++++
gcc/testsuite/g++.dg/cpp0x/noexcept86.C | 25 +++++++++++++++++++
4 files changed, 68 insertions(+), 13 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/noexcept85.C
create mode 100644 gcc/testsuite/g++.dg/cpp0x/noexcept86.C
diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc
index dce4caf8981..4b2b27bdd0d 100644
--- a/gcc/cp/name-lookup.cc
+++ b/gcc/cp/name-lookup.cc
@@ -8664,10 +8664,14 @@ maybe_push_to_top_level (tree d)
{
/* Push if D isn't function-local, or is a lambda function, for which name
resolution is already done. */
- bool push_to_top
- = !(current_function_decl
- && !LAMBDA_FUNCTION_P (d)
- && decl_function_context (d) == current_function_decl);
+ const bool push_to_top
+ = (LAMBDA_FUNCTION_P (d)
+ || (TREE_CODE (d) == TYPE_DECL
+ && TREE_TYPE (d)
+ && LAMBDA_TYPE_P (TREE_TYPE (d)))
+ || !current_function_decl
+ || (!decl_function_context (d)
+ && decl_function_context (d) != current_function_decl));
if (push_to_top)
push_to_top_level ();
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 8cf0d5b7a8d..7b00a8615d2 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -26855,7 +26855,7 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
}
else if (push_tinst_level (fn))
{
- push_to_top_level ();
+ const bool push_to_top = maybe_push_to_top_level (fn);
push_access_scope (fn);
push_deferring_access_checks (dk_no_deferred);
input_location = DECL_SOURCE_LOCATION (fn);
@@ -26878,17 +26878,10 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
if (orig_fn)
++processing_template_decl;
- ++cp_unevaluated_operand;
- ++c_inhibit_evaluation_warnings;
- ++cp_noexcept_operand;
/* Do deferred instantiation of the noexcept-specifier. */
noex = tsubst_expr (DEFERRED_NOEXCEPT_PATTERN (noex),
DEFERRED_NOEXCEPT_ARGS (noex),
tf_warning_or_error, fn);
- --cp_unevaluated_operand;
- --c_inhibit_evaluation_warnings;
- --cp_noexcept_operand;
-
/* Build up the noexcept-specification. */
spec = build_noexcept_spec (noex, tf_warning_or_error);
@@ -26898,7 +26891,7 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
pop_deferring_access_checks ();
pop_access_scope (fn);
pop_tinst_level ();
- pop_from_top_level ();
+ maybe_pop_from_top_level (push_to_top);
}
else
spec = noexcept_false_spec;
diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept85.C
b/gcc/testsuite/g++.dg/cpp0x/noexcept85.C
new file mode 100644
index 00000000000..b415bb46bc9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/noexcept85.C
@@ -0,0 +1,33 @@
+// PR c++/114349
+// { dg-do compile { target c++11 } }
+
+using A = struct {};
+template <template <typename> class, typename, typename>
+using B = A;
+template <typename T>
+using C = typename T::D;
+struct E {
+ using D = B<C, int, A>;
+};
+template <class> constexpr bool foo (A) { return false; }
+template <class T> struct F {
+ using G = T;
+ using H = E;
+ F(const F &);
+ void operator=(F) noexcept(foo <G> (H::D{}));
+};
+template <typename, typename, typename>
+using I = F<int>;
+template <typename K, typename V, typename H = K>
+using J = I<K, V, H>;
+struct K {
+ typedef J<long, char> L;
+ L k;
+ K();
+};
+struct M {
+ bool bar () const;
+ K::L m;
+};
+K n;
+bool M::bar () const { n.k = m; return true; }
diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept86.C
b/gcc/testsuite/g++.dg/cpp0x/noexcept86.C
new file mode 100644
index 00000000000..2d040c090f5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/noexcept86.C
@@ -0,0 +1,25 @@
+// PR c++/114349
+// { dg-do compile { target c++14 } }
+
+struct B
+{
+ int i;
+};
+
+template <bool BA>
+void
+goo ()
+{
+ constexpr bool is_yes = BA;
+ struct C
+ {
+ static auto g(B b) noexcept(is_yes) { }
+ };
+ C::g({});
+}
+
+void
+x ()
+{
+ goo<false>();
+}
base-commit: 65b7d1862e11784a0ce67ab758e06dd8aa65b181
--
2.44.0
