[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, 5 insertions, 5 deletions

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 41c8a4c52a..4bf17a6d88 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -184,6 +184,11 @@ DiagnoseAvailabilityOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc,
   if (AvailabilityResult Result =
           S.ShouldDiagnoseAvailabilityOfDecl(D, ContextVersion, &Message)) {
 
+    if (Result == AR_NotYetIntroduced && S.getCurFunctionOrMethodDecl()) {
+      S.getEnclosingFunction()->HasPotentialAvailabilityViolations = true;
+      return;
+    }
+
     const ObjCPropertyDecl *ObjCPDecl = nullptr;
     if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
       if (const ObjCPropertyDecl *PD = MD->findPropertyDecl()) {
@@ -15198,11 +15203,6 @@ ExprResult Sema::ActOnObjCAvailabilityCheckExpr(
   VersionTuple Version;
   if (Spec != AvailSpecs.end())
     Version = Spec->getVersion();
-  else
-    // This is the '*' case in @available. We should diagnose this; the
-    // programmer should explicitly account for this case if they target this
-    // platform.
-    Diag(AtLoc, diag::warn_available_using_star_case) << RParen << Platform;
 
   return new (Context)
       ObjCAvailabilityCheckExpr(Version, AtLoc, RParen, Context.BoolTy);