From 876fa432ef4074053fa65b1855e7d43320515576 Mon Sep 17 00:00:00 2001
From: Marek Polacek <polacek@redhat.com>
Date: Thu, 15 Feb 2024 17:07:43 -0500
Subject: [PATCH] c++: wrong looser excep spec for dep noexcept [PR113158]
Here we find ourselves in maybe_check_overriding_exception_spec in
a template context where we can't instantiate a dependent noexcept.
That's OK, but we have to defer the checking otherwise we give wrong
errors.
PR c++/113158
gcc/cp/ChangeLog:
* search.cc (maybe_check_overriding_exception_spec): Defer checking
when a noexcept couldn't be instantiated & evaluated to false/true.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/noexcept83.C: New test.
---
gcc/cp/search.cc | 11 ++++++++
gcc/testsuite/g++.dg/cpp0x/noexcept83.C | 37 +++++++++++++++++++++++++
2 files changed, 48 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/noexcept83.C
diff --git a/gcc/cp/search.cc b/gcc/cp/search.cc
index c948839dc533..827f48e8604f 100644
--- a/gcc/cp/search.cc
+++ b/gcc/cp/search.cc
@@ -1975,6 +1975,17 @@ maybe_check_overriding_exception_spec (tree overrider, tree basefn)
|| UNPARSED_NOEXCEPT_SPEC_P (over_throw))
return true;
+ /* We also have to defer checking when we're in a template and couldn't
+ instantiate & evaluate the noexcept to true/false. */
+ if (processing_template_decl)
+ if ((base_throw
+ && base_throw != noexcept_true_spec
+ && base_throw != noexcept_false_spec)
+ || (over_throw
+ && over_throw != noexcept_true_spec
+ && over_throw != noexcept_false_spec))
+ return true;
+
if (!comp_except_specs (base_throw, over_throw, ce_derived))
{
auto_diagnostic_group d;
diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept83.C b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C
new file mode 100644
index 000000000000..47832bbb44d3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C
@@ -0,0 +1,37 @@
+// PR c++/113158
+// { dg-do compile { target c++11 } }
+
+template<typename T>
+struct V {
+ static constexpr bool t = false;
+};
+struct base {
+ virtual int f() = 0;
+};
+
+template<typename T>
+struct derived : base {
+ int f() noexcept(V<T>::t) override;
+};
+
+struct base2 {
+ virtual int f() noexcept = 0;
+};
+
+template<bool B>
+struct W {
+ static constexpr bool t = B;
+};
+
+template<bool B>
+struct derived2 : base2 {
+ int f() noexcept(W<B>::t) override; // { dg-error "looser exception specification" }
+};
+
+void
+g ()
+{
+ derived<int> d1;
+ derived2<false> d2; // { dg-message "required from here" }
+ derived2<true> d3;
+}
--
GitLab