[PATCH] c++: Fix bogus warning in deprecated namespace [PR99318]
Marek Polacek
polacek@redhat.com
Wed Mar 10 03:22:11 GMT 2021
In GCC 10, I introduced cp_warn_deprecated_use_scopes so that we can
handle attribute deprecated on a namespace declaration. This
function walks the decl's contexts so that we warn for code like
namespace [[deprecated]] N { struct S { }; }
N::S s;
We call cp_warn_deprecated_use_scopes when we encounter a TYPE_DECL.
But in the following testcase we have a TYPE_DECL whose context is
a deprecated function; that itself is not a reason to warn. This
patch limits for which entities we call cp_warn_deprecated_use;
essentially it's what can follow ::.
I noticed that we didn't test that
struct [[deprecated]] S { static void fn(); };
S::fn();
produces the expected warning, so I've added gen-attrs-73.C.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/10?
gcc/cp/ChangeLog:
PR c++/99318
* decl2.c (cp_warn_deprecated_use_scopes): Only call
cp_warn_deprecated_use when decl is a namespace, class, or enum.
gcc/testsuite/ChangeLog:
PR c++/99318
* g++.dg/cpp0x/attributes-namespace6.C: New test.
* g++.dg/cpp0x/gen-attrs-73.C: New test.
---
gcc/cp/decl2.c | 3 ++-
.../g++.dg/cpp0x/attributes-namespace6.C | 21 +++++++++++++++++++
gcc/testsuite/g++.dg/cpp0x/gen-attrs-73.C | 20 ++++++++++++++++++
3 files changed, 43 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/attributes-namespace6.C
create mode 100644 gcc/testsuite/g++.dg/cpp0x/gen-attrs-73.C
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index c46100de89a..ef79f6cc6d1 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -5529,7 +5529,8 @@ cp_warn_deprecated_use_scopes (tree scope)
&& scope != error_mark_node
&& scope != global_namespace)
{
- if (cp_warn_deprecated_use (scope))
+ if ((TREE_CODE (scope) == NAMESPACE_DECL || OVERLOAD_TYPE_P (scope))
+ && cp_warn_deprecated_use (scope))
return;
if (TYPE_P (scope))
scope = CP_TYPE_CONTEXT (scope);
diff --git a/gcc/testsuite/g++.dg/cpp0x/attributes-namespace6.C b/gcc/testsuite/g++.dg/cpp0x/attributes-namespace6.C
new file mode 100644
index 00000000000..2fbc8e1158f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/attributes-namespace6.C
@@ -0,0 +1,21 @@
+// PR c++/99318
+// { dg-do compile { target c++11 } }
+
+template <typename T>
+struct S {
+ [[deprecated("foo")]] unsigned m_fn (char const chr)
+ {
+ using index_t = unsigned;
+ return T::arr[static_cast<index_t>(chr)]; // { dg-bogus "deprecated" }
+ }
+};
+
+extern unsigned int arr[];
+
+struct R {
+ [[deprecated("foo")]] unsigned m_fn (char const chr)
+ {
+ using index_t = unsigned;
+ return arr[static_cast<index_t>(chr)]; // { dg-bogus "deprecated" }
+ }
+};
diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-73.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-73.C
new file mode 100644
index 00000000000..75f4077af7b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-73.C
@@ -0,0 +1,20 @@
+// { dg-do compile { target c++11 } }
+// Test attribute deprecated on :: with class, enum, and namespace.
+
+struct [[deprecated]] S { static void fn(); static const int s = 0; };
+union [[deprecated]] U { static void fn(); static const int u = 0; };
+enum [[deprecated]] E { X };
+enum class [[deprecated]] SE { Y };
+namespace [[deprecated]] N { struct S { }; }
+
+void
+g ()
+{
+ S::fn(); // { dg-warning "deprecated" }
+ (void) S::s; // { dg-warning "deprecated" }
+ U::fn(); // { dg-warning "deprecated" }
+ (void) U::u; // { dg-warning "deprecated" }
+ (void) E::X; // { dg-warning "deprecated" }
+ (void) SE::Y; // { dg-warning "deprecated" }
+ N::S s; // { dg-warning "deprecated" }
+}
base-commit: 63d74fed4566f1de583c368ecb9e2fc423fb1c87
--
2.29.2
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