[clang] [Clang] Minimal support for availability attributes on partial specializations (PR #138426)

[via cfe-commits]

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@@ -72,3 +72,58 @@ template <class B1> struct B {
 
 template struct B<A>; // expected-note {{requested here}}
 } // namespace GH58547
+
+
+namespace GH44496 {
+  template <class> struct my_template {
+    using type = void;
+};
+
+template <class T>
+struct [[deprecated("primary")]] deprecated { // #deprecated-primary-marked-here
+    using type = T;
+};
+
+template <class T>
+struct my_template<volatile T> : deprecated<T> {}; // #deprecated-primary-base
+
+template <class T>
+struct [[deprecated("specialization")]] my_template<const T> : deprecated<const T> {}; // #my_template-explicit-here
+
+
+template <class T> using my_template_t = typename my_template<T>::type; // #deprecated-my-template-alias
+
+// We cannot warn on X because no instantiation has taken place yet
+using X  = my_template<volatile int>;
+
+// Because we already warn on the attribute on the plimary template, we ignore the attribute on the specialization
+using Y  = my_template_t<const int>;
+// expected-warning@#deprecated-primary-base {{'deprecated<int>' is deprecated: primary}} \
+// expected-note at -1 {{in instantiation of template type alias}} \
+// expected-note@#deprecated-primary-marked-here {{has been explicitly marked deprecated here}}
+
+using Z  = my_template_t<volatile int>;
+// expected-warning@#deprecated-my-template-alias {{'my_template<const int>' is deprecated: specialization}} \
+// expected-note@#my_template-explicit-here {{'my_template<const int>' has been explicitly marked deprecated here}} \
+// expected-note@#deprecated-my-template-alias {{in instantiation of template class 'GH44496::my_template<volatile int>' requested here}} \
+// expected-note at -1 {{in instantiation of template type alias 'my_template_t' requested here}}
+
+template <class T>
+struct primary_not_deprecated {
+    using type = T;
+};
+template <class T>
+struct [[deprecated("specialization")]] primary_not_deprecated<volatile T> : deprecated<T> {};
+// expected-note at -1 {{'primary_not_deprecated<volatile int>' has been explicitly marked deprecated here}}
+
+// We cannot warn on S1 because no instantiation has taken place yet
+using S1 = primary_not_deprecated<volatile int>;
+
+
+using S2 = primary_not_deprecated<volatile int>;
+
+X x;
+Z z;
+S2 s2;
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cor3ntin wrote:

I added the test

https://github.com/llvm/llvm-project/pull/138426