[ObjC] Warn on unguarded use of partial declaration

This commit adds a traversal of the AST after Sema of a function that diagnoses
unguarded references to declarations that are partially available (based on
availability attributes). This traversal is only done when we would otherwise
emit -Wpartial-availability.

This commit is part of a feature I proposed here:
http://lists.llvm.org/pipermail/cfe-dev/2016-July/049851.html

Differential revision: https://reviews.llvm.org/D23003

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278826 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 1 deletions

diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 4a5c0211a1..d4802351d8 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -95,8 +95,9 @@ def CXX11CompatDeprecatedWritableStr :
 def DeprecatedAttributes : DiagGroup<"deprecated-attributes">;
 def DeprecatedDeclarations : DiagGroup<"deprecated-declarations">;
 def UnavailableDeclarations : DiagGroup<"unavailable-declarations">;
-def PartialAvailability : DiagGroup<"partial-availability">;
 def UnguardedAvailability : DiagGroup<"unguarded-availability">;
+// partial-availability is an alias of unguarded-availability.
+def : DiagGroup<"partial-availability", [UnguardedAvailability]>;
 def DeprecatedImplementations :DiagGroup<"deprecated-implementations">;
 def DeprecatedIncrementBool : DiagGroup<"deprecated-increment-bool">;
 def DeprecatedRegister : DiagGroup<"deprecated-register">;