Fix several problems with protected access control:

  - The [class.protected] restriction is non-trivial for any instance
    member, even if the access lacks an object (for example, if it's
    a pointer-to-member constant).  In this case, it is equivalent to
    requiring the naming class to equal the context class.
  - The [class.protected] restriction applies to accesses to constructors
    and destructors.  A protected constructor or destructor can only be
    used to create or destroy a base subobject, as a direct result.
  - Several places were dropping or misapplying object information.

The standard could really be much clearer about what the object type is
supposed to be in some of these accesses.  Usually it's easy enough to
find a reasonable answer, but still, the standard makes a very confident
statement about accesses to instance members only being possible in
either pointer-to-member literals or member access expressions, which
just completely ignores concepts like constructor and destructor
calls, using declarations, unevaluated field references, etc.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154248 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 2 deletions

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index ffe7be300a..a832087e27 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -884,8 +884,13 @@ def note_access_natural : Note<
 def note_access_constrained_by_path : Note<
   "constrained by %select{|implicitly }1%select{private|protected}0"
   " inheritance here">;
-def note_access_protected_restricted : Note<
-  "object type %select{|%1 }0must derive from context type %2">;
+def note_access_protected_restricted_noobject : Note<
+  "must name member using the type of the current context %0">;
+def note_access_protected_restricted_ctordtor : Note<
+  "protected %select{constructor|destructor}0 can only be used to "
+  "%select{construct|destroy}0 a base class subobject">;
+def note_access_protected_restricted_object : Note<
+  "can only access this member on an object of type %0">;
 def warn_cxx98_compat_sfinae_access_control : Warning<
   "substitution failure due to access control is incompatible with C++98">,
   InGroup<CXX98Compat>, DefaultIgnore, NoSFINAE;