Make diagnostic for use of default member initializer before enclosing class is

complete a little more general; it is produced in other cases than the one that
it previously talked about.

llvm-svn: 287713

Author: zygoloid

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -7099,12 +7099,11 @@ def err_in_class_initializer_literal_type : Error<
   "'constexpr' specifier">;
 def err_in_class_initializer_non_constant : Error<
   "in-class initializer for static data member is not a constant expression">;
-def err_in_class_initializer_not_yet_parsed
-    : Error<"cannot use defaulted default constructor of %0 within the class "
-            "outside of member functions because %1 has an initializer">;
-def err_in_class_initializer_not_yet_parsed_outer_class
-    : Error<"cannot use defaulted default constructor of %0 within "
-            "%1 outside of member functions because %2 has an initializer">;
+def err_in_class_initializer_not_yet_parsed : Error<
+  "default member initializer for %1 needed within definition of enclosing "
+  "class %0 outside of member functions">;
+def note_in_class_initializer_not_yet_parsed : Note<
+  "default member initializer declared here">;
 def err_in_class_initializer_cycle
     : Error<"default member initializer for %0 uses itself">;
 def err_exception_spec_cycle

clang/lib/Sema/SemaDeclCXX.cpp

@@ -12378,14 +12378,9 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
   // constructor before the initializer is lexically complete will ultimately
   // come here at which point we can diagnose it.
   RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
-  if (OutermostClass == ParentRD) {
-    Diag(Field->getLocEnd(), diag::err_in_class_initializer_not_yet_parsed)
-        << ParentRD << Field;
-  } else {
-    Diag(Field->getLocEnd(),
-         diag::err_in_class_initializer_not_yet_parsed_outer_class)
-        << ParentRD << OutermostClass << Field;
-  }
+  Diag(Loc, diag::err_in_class_initializer_not_yet_parsed)
+      << OutermostClass << Field;
+  Diag(Field->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
 
   return ExprError();
 }

clang/lib/Sema/SemaTemplateInstantiate.cpp

@@ -2198,14 +2198,10 @@ bool Sema::InstantiateInClassInitializer(
   if (!OldInit) {
     RecordDecl *PatternRD = Pattern->getParent();
     RecordDecl *OutermostClass = PatternRD->getOuterLexicalRecordContext();
-    if (OutermostClass == PatternRD) {
-      Diag(Pattern->getLocEnd(), diag::err_in_class_initializer_not_yet_parsed)
-          << PatternRD << Pattern;
-    } else {
-      Diag(Pattern->getLocEnd(),
-           diag::err_in_class_initializer_not_yet_parsed_outer_class)
-          << PatternRD << OutermostClass << Pattern;
-    }
+    Diag(PointOfInstantiation,
+         diag::err_in_class_initializer_not_yet_parsed)
+        << OutermostClass << Pattern;
+    Diag(Pattern->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
     Instantiation->setInvalidDecl();
     return true;
   }

clang/test/SemaCXX/constant-expression-cxx11.cpp

@@ -1862,8 +1862,8 @@ namespace ZeroSizeTypes {
 namespace BadDefaultInit {
   template<int N> struct X { static const int n = N; };
 
-  struct A {
-    int k = // expected-error {{cannot use defaulted default constructor of 'A' within the class outside of member functions because 'k' has an initializer}}
+  struct A { // expected-error {{default member initializer for 'k' needed within definition of enclosing class}}
+    int k = // expected-note {{default member initializer declared here}}
         X<A().k>::n; // expected-error {{not a constant expression}} expected-note {{implicit default constructor for 'BadDefaultInit::A' first required here}}
   };
 

clang/test/SemaCXX/cxx1y-initializer-aggregates.cpp

@@ -61,3 +61,19 @@ namespace nested_aggregate_init {
   };
   static_assert(B(6).f() == 18, "");
 }
+
+namespace use_self {
+  struct FibTree {
+    int n;
+    FibTree *l = // expected-note {{declared here}}
+      n > 1 ? new FibTree{n-1} : &fib0; // expected-error {{default member initializer for 'l' needed}}
+    FibTree *r = // expected-note {{declared here}}
+      n > 2 ? new FibTree{n-2} : &fib0; // expected-error {{default member initializer for 'r' needed}}
+    int v = l->v + r->v;
+
+    static FibTree fib0;
+  };
+  FibTree FibTree::fib0{0, nullptr, nullptr, 1};
+
+  int fib(int n) { return FibTree{n}.v; }
+}

clang/test/SemaCXX/implicit-exception-spec.cpp

@@ -16,31 +16,31 @@ namespace InClassInitializers {
   // Noexcept::Noexcept is not declared constexpr, therefore noexcept(Noexcept())
   // is false.
   bool ThrowSomething() noexcept(false);
-  struct ConstExpr {
-    bool b = noexcept(ConstExpr()) && ThrowSomething(); // expected-error {{cannot use defaulted default constructor of 'ConstExpr' within the class outside of member functions}}
+  struct ConstExpr { // expected-error {{default member initializer for 'b' needed}}
+    bool b = noexcept(ConstExpr()) && ThrowSomething(); // expected-note {{declared here}}
   // expected-note@-1 {{implicit default constructor for 'InClassInitializers::ConstExpr' first required here}}
   };
 
   // Much more obviously broken: we can't parse the initializer without already
   // knowing whether it produces a noexcept expression.
-  struct TemplateArg {
-    int n = ExceptionIf<noexcept(TemplateArg())>::f(); // expected-error {{cannot use defaulted default constructor of 'TemplateArg' within the class outside of member functions}}
+  struct TemplateArg { // expected-error {{default member initializer for 'n' needed}}
+    int n = ExceptionIf<noexcept(TemplateArg())>::f(); // expected-note {{declared here}}
     // expected-note@-1 {{implicit default constructor for 'InClassInitializers::TemplateArg' first required here}}
   };
 
   // And within a nested class.
   struct Nested { // expected-note {{implicit default constructor for 'InClassInitializers::Nested::Inner' first required here}}
-    struct Inner {
-      // expected-error@+1 {{cannot use defaulted default constructor of 'Inner' within 'Nested' outside of member functions}}
-      int n = ExceptionIf<noexcept(Nested())>::f(); // expected-note {{implicit default constructor for 'InClassInitializers::Nested' first required here}}
+    struct Inner { // expected-error {{default member initializer for 'n' needed}}
+      int n = // expected-note {{declared here}}
+        ExceptionIf<noexcept(Nested())>::f(); // expected-note {{implicit default constructor for 'InClassInitializers::Nested' first required here}}
     } inner;
   };
 
   struct Nested2 { // expected-error {{implicit default constructor for 'InClassInitializers::Nested2' must explicitly initialize the member 'inner' which does not have a default constructor}}
     struct Inner;
     int n = Inner().n; // expected-note {{implicit default constructor for 'InClassInitializers::Nested2::Inner' first required here}}
-    struct Inner { // expected-note {{declared here}}
-      // expected-error@+1 {{cannot use defaulted default constructor of 'Inner' within 'Nested2' outside of member functions}}
+    struct Inner { // expected-error {{initializer for 'n' needed}} expected-note {{declared here}}
+      // expected-note@+1 {{declared here}}
       int n = ExceptionIf<noexcept(Nested2())>::f();
       // expected-note@-1 {{implicit default constructor for 'InClassInitializers::Nested2' first required here}}
     } inner; // expected-note {{member is declared here}}

clang/test/SemaCXX/member-init.cpp

@@ -13,8 +13,8 @@ class NoWarning {
 
 bool b();
 int k;
-struct Recurse {
-  int &n = // expected-error {{cannot use defaulted default constructor of 'Recurse' within the class outside of member functions because 'n' has an initializer}}
+struct Recurse { // expected-error {{initializer for 'n' needed}}
+  int &n = // expected-note {{declared here}}
       b() ?
       Recurse().n : // expected-note {{implicit default constructor for 'Recurse' first required here}}
       k;
@@ -128,8 +128,8 @@ A::A() {}
 namespace template_default_ctor {
 struct A {
   template <typename T>
-  struct B {
-    int m1 = 0; // expected-error {{cannot use defaulted default constructor of 'B' within 'A' outside of member functions because 'm1' has an initializer}}
+  struct B { // expected-error {{initializer for 'm1' needed}}
+    int m1 = 0; // expected-note {{declared here}}
   };
   // expected-note@+1 {{implicit default constructor for 'template_default_ctor::A::B<int>' first required here}}
   enum { NOE = noexcept(B<int>()) };
@@ -138,8 +138,8 @@ struct A {
 
 namespace default_ctor {
 struct A {
-  struct B {
-    int m1 = 0; // expected-error {{cannot use defaulted default constructor of 'B' within 'A' outside of member functions because 'm1' has an initializer}}
+  struct B { // expected-error {{initializer for 'm1' needed}}
+    int m1 = 0; // expected-note {{declared here}}
   };
   // expected-note@+1 {{implicit default constructor for 'default_ctor::A::B' first required here}}
   enum { NOE = noexcept(B()) };
@@ -150,12 +150,12 @@ namespace member_template {
 struct A {
   template <typename T>
   struct B {
-    struct C {
-      int m1 = 0; // expected-error {{cannot use defaulted default constructor of 'C' within 'A' outside of member functions because 'm1' has an initializer}}
+    struct C { // expected-error {{initializer for 'm1' needed}}
+      int m1 = 0; // expected-note {{declared here}}
     };
     template <typename U>
-    struct D {
-      int m1 = 0; // expected-error {{cannot use defaulted default constructor of 'D' within 'A' outside of member functions because 'm1' has an initializer}}
+    struct D { // expected-error {{initializer for 'm1' needed}}
+      int m1 = 0; // expected-note {{declared here}}
     };
   };
   enum {