1 files changed, 108 insertions, 0 deletions
diff --git a/test/CXX/temp/temp.deduct.guide/p1.cpp b/test/CXX/temp/temp.deduct.guide/p1.cpp
new file mode 100644
index 000000000000..c0a2ba1129e2
--- /dev/null
+++ b/test/CXX/temp/temp.deduct.guide/p1.cpp
@@ -0,0 +1,108 @@
+// RUN: %clang_cc1 -std=c++1z -fcxx-exceptions -verify %s
+// RUN: %clang_cc1 -std=c++1z -fcxx-exceptions -verify %s -DCLASS
+
+#ifdef CLASS
+struct Outer {
+#endif
+
+template<typename> struct A {};
+
+// Valid forms.
+A(int(&)[1]) -> A<int>;
+explicit A(int(&)[2]) -> A<int>;
+
+// Declarator pieces are not OK.
+*A(int(&)[3]) -> A<int>; // expected-error {{cannot specify any part of a return type in the declaration of a deduction guide}}
+&A(int(&)[4]) -> A<int>; // expected-error {{cannot specify any part of a return type in the declaration of a deduction guide}}
+A(int(&)[5])[3] -> A<int>;
+#ifdef CLASS // FIXME: These diagnostics are both pretty bad.
+// expected-error@-2 {{function cannot return array type}} expected-error@-2 {{';'}}
+#else
+// expected-error@-4 {{expected function body after function declarator}}
+#endif
+
+(A[3])(int(&)[5][1]) -> A<int>; // expected-error {{'<deduction guide for A>' cannot be the name of a variable}}
+#ifndef CLASS
+// expected-error@-2 {{declared as array of functions}}
+#endif
+(*A)(int(&)[5][2]) -> A<int>; // expected-error {{'<deduction guide for A>' cannot be the name of a variable}}
+(&A)(int(&)[5][3]) -> A<int>; // expected-error {{'<deduction guide for A>' cannot be the name of a variable}}
+(*A(int))(int(&)[5][4]) -> A<int>; // expected-error {{cannot specify any part of a return type in the declaration of a deduction guide}}
+
+// (Pending DR) attributes and parens around the declarator-id are OK.
+[[deprecated]] A(int(&)[6]) [[]] -> A<int> [[]];
+A [[]] (int(&)[7]) -> A<int>;
+(A)(int(&)[8]) -> A<int>;
+
+// ... but the trailing-return-type is part of the function-declarator as normal
+(A(int(&)[9])) -> A<int>;
+#ifdef CLASS // FIXME: These diagnostics are both pretty bad.
+// expected-error@-2 {{deduction guide declaration without trailing return type}} expected-error@-2 {{';'}}
+#else
+// expected-error@-4 {{expected function body after function declarator}}
+#endif
+(A(int(&)[10]) -> A<int>); // expected-error {{trailing return type may not be nested within parentheses}}
+
+// A trailing-return-type is mandatory.
+A(int(&)[11]); // expected-error {{deduction guide declaration without trailing return type}}
+
+// No type specifier is permitted; we don't even parse such cases as a deduction-guide.
+int A(int) -> A<int>; // expected-error {{function with trailing return type must specify return type 'auto', not 'int'}}
+template<typename T> struct B {}; // expected-note {{here}}
+auto B(int) -> B<int>; // expected-error {{redefinition of 'B' as different kind of symbol}}
+
+// No storage class specifier, function specifier, ...
+friend A(int(&)[20]) -> A<int>;
+#ifdef CLASS
+// expected-error@-2 {{cannot declare a deduction guide as a friend}}
+#else
+// expected-error@-4 {{'friend' used outside of class}}
+#endif
+typedef A(int(&)[21]) -> A<int>; // expected-error {{deduction guide cannot be declared 'typedef'}}
+constexpr A(int(&)[22]) -> A<int>; // expected-error {{deduction guide cannot be declared 'constexpr'}}
+inline A(int(&)[23]) -> A<int>; // expected-error {{deduction guide cannot be declared 'inline'}}
+static A(int(&)[24]) -> A<int>; // expected-error {{deduction guide cannot be declared 'static'}}
+thread_local A(int(&)[25]) -> A<int>; // expected-error {{'thread_local' is only allowed on variable declarations}}
+extern A(int(&)[26]) -> A<int>;
+#ifdef CLASS
+// expected-error@-2 {{storage class specified for a member}}
+#else
+// expected-error@-4 {{deduction guide cannot be declared 'extern'}}
+#endif
+mutable A(int(&)[27]) -> A<int>; // expected-error-re {{{{'mutable' cannot be applied to|illegal storage class on}} function}}
+virtual A(int(&)[28]) -> A<int>; // expected-error {{'virtual' can only appear on non-static member functions}}
+const A(int(&)[28]) -> A<int>; // expected-error {{deduction guide cannot be declared 'const'}}
+
+const volatile static constexpr inline A(int(&)[29]) -> A<int>; // expected-error {{deduction guide cannot be declared 'static inline constexpr const volatile'}}
+
+A(int(&)[30]) const -> A<int>; // expected-error {{deduction guide cannot have 'const' qualifier}}
+
+// No definition is allowed.
+A(int(&)[40]) -> A<int> {} // expected-error {{deduction guide cannot have a function definition}}
+A(int(&)[41]) -> A<int> = default; // expected-error {{deduction guide cannot have a function definition}} expected-error {{only special member functions may be defaulted}}
+A(int(&)[42]) -> A<int> = delete; // expected-error {{deduction guide cannot have a function definition}}
+A(int(&)[43]) -> A<int> try {} catch (...) {} // expected-error {{deduction guide cannot have a function definition}}
+
+#ifdef CLASS
+};
+#endif
+
+namespace ExplicitInst {
+  // Explicit instantiation / specialization is not permitted.
+  template<typename T> struct B {};
+  template<typename T> B(T) -> B<T>;
+  template<> B(int) -> B<int>; // expected-error {{deduction guide cannot be explicitly specialized}}
+  extern template B(float) -> B<float>; // expected-error {{deduction guide cannot be explicitly instantiated}}
+  template B(char) -> B<char>; // expected-error {{deduction guide cannot be explicitly instantiated}}
+
+  // An attempt at partial specialization doesn't even parse as a deduction-guide.
+  template<typename T> B<T*>(T*) -> B<T*>; // expected-error 1+{{}} expected-note 0+{{}}
+
+  struct X {
+    template<typename T> struct C {};
+    template<typename T> C(T) -> C<T>;
+    template<> C(int) -> C<int>; // expected-error {{explicit specialization of '<deduction guide for C>' in class scope}}
+    extern template C(float) -> C<float>; // expected-error {{expected member name or ';'}}
+    template C(char) -> C<char>; // expected-error {{expected '<' after 'template'}}
+  };
+}