Implements gcc's -Wstrict-selector-match.
(radar 8127244).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110622 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index d22714a..1e5da3d 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -1677,7 +1677,8 @@
   /// true, or false, accordingly.
   bool MatchTwoMethodDeclarations(const ObjCMethodDecl *Method,
                                   const ObjCMethodDecl *PrevMethod,
-                                  bool matchBasedOnSizeAndAlignment = false);
+                                  bool matchBasedOnSizeAndAlignment = false,
+                                  bool matchBasedOnStrictEqulity = false);
 
   /// MatchAllMethodDeclarations - Check methods declaraed in interface or
   /// or protocol against those declared in their implementations.
@@ -1698,6 +1699,7 @@
   /// LookupMethodInGlobalPool - Returns the instance or factory method and
   /// optionally warns if there are multiple signatures.
   ObjCMethodDecl *LookupMethodInGlobalPool(Selector Sel, SourceRange R,
+                                           bool receiverIdOrClass,
                                            bool warn, bool instance);
 
 public:
@@ -1717,15 +1719,19 @@
   /// LookupInstanceMethodInGlobalPool - Returns the method and warns if
   /// there are multiple signatures.
   ObjCMethodDecl *LookupInstanceMethodInGlobalPool(Selector Sel, SourceRange R,
+                                                   bool receiverIdOrClass=false,
                                                    bool warn=true) {
-    return LookupMethodInGlobalPool(Sel, R, warn, /*instance*/true);
+    return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass, 
+                                    warn, /*instance*/true);
   }
 
   /// LookupFactoryMethodInGlobalPool - Returns the method and warns if
   /// there are multiple signatures.
   ObjCMethodDecl *LookupFactoryMethodInGlobalPool(Selector Sel, SourceRange R,
+                                                  bool receiverIdOrClass=false,
                                                   bool warn=true) {
-    return LookupMethodInGlobalPool(Sel, R, warn, /*instance*/false);
+    return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass,
+                                    warn, /*instance*/false);
   }
 
   /// LookupImplementedMethodInGlobalPool - Returns the method which has an
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 283376b..160bc19 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -1100,13 +1100,14 @@
 /// TODO: Handle protocol list; such as id<p1,p2> in type comparisons
 bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *Method,
                                       const ObjCMethodDecl *PrevMethod,
-                                      bool matchBasedOnSizeAndAlignment) {
+                                      bool matchBasedOnSizeAndAlignment,
+                                      bool matchBasedOnStrictEqulity) {
   QualType T1 = Context.getCanonicalType(Method->getResultType());
   QualType T2 = Context.getCanonicalType(PrevMethod->getResultType());
 
   if (T1 != T2) {
     // The result types are different.
-    if (!matchBasedOnSizeAndAlignment)
+    if (!matchBasedOnSizeAndAlignment || matchBasedOnStrictEqulity)
       return false;
     // Incomplete types don't have a size and alignment.
     if (T1->isIncompleteType() || T2->isIncompleteType())
@@ -1126,7 +1127,7 @@
     T2 = Context.getCanonicalType((*PrevI)->getType());
     if (T1 != T2) {
       // The result types are different.
-      if (!matchBasedOnSizeAndAlignment)
+      if (!matchBasedOnSizeAndAlignment || matchBasedOnStrictEqulity)
         return false;
       // Incomplete types don't have a size and alignment.
       if (T1->isIncompleteType() || T2->isIncompleteType())
@@ -1188,8 +1189,8 @@
   Entry.Next = new (Mem) ObjCMethodList(Method, Entry.Next);
 }
 
-// FIXME: Finish implementing -Wno-strict-selector-match.
 ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
+                                               bool receiverIdOrClass,
                                                bool warn, bool instance) {
   GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
   if (Pos == MethodPool.end()) {
@@ -1201,15 +1202,30 @@
 
   ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
 
+  bool strictSelectorMatch = receiverIdOrClass && warn &&
+    (Diags.getDiagnosticLevel(diag::warn_strict_multiple_method_decl) != 
+      Diagnostic::Ignored);
   if (warn && MethList.Method && MethList.Next) {
     bool issueWarning = false;
-    for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next) {
-      // This checks if the methods differ by size & alignment.
-      if (!MatchTwoMethodDeclarations(MethList.Method, Next->Method, true))
-        issueWarning = true;
-    }
+    if (strictSelectorMatch)
+      for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next) {
+        // This checks if the methods differ in type mismatch.
+        if (!MatchTwoMethodDeclarations(MethList.Method, Next->Method, false, true))
+          issueWarning = true;
+      }
+
+    if (!issueWarning)
+      for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next) {
+        // This checks if the methods differ by size & alignment.
+        if (!MatchTwoMethodDeclarations(MethList.Method, Next->Method, true))
+          issueWarning = true;
+      }
+
     if (issueWarning) {
-      Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
+      if (strictSelectorMatch)
+        Diag(R.getBegin(), diag::warn_strict_multiple_method_decl) << Sel << R;
+      else
+        Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
       Diag(MethList.Method->getLocStart(), diag::note_using)
         << MethList.Method->getSourceRange();
       for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next)
diff --git a/lib/Sema/SemaExprObjC.cpp b/lib/Sema/SemaExprObjC.cpp
index bf933c3..df97041 100644
--- a/lib/Sema/SemaExprObjC.cpp
+++ b/lib/Sema/SemaExprObjC.cpp
@@ -153,7 +153,7 @@
                                                    SourceLocation LParenLoc,
                                                    SourceLocation RParenLoc) {
   ObjCMethodDecl *Method = LookupInstanceMethodInGlobalPool(Sel,
-                             SourceRange(LParenLoc, RParenLoc), false);
+                             SourceRange(LParenLoc, RParenLoc), false, false);
   if (!Method)
     Method = LookupFactoryMethodInGlobalPool(Sel,
                                           SourceRange(LParenLoc, RParenLoc));
@@ -863,13 +863,17 @@
 
   if (!Method) {
     // Handle messages to id.
-    if (ReceiverType->isObjCIdType() || ReceiverType->isBlockPointerType() ||
+    bool receiverIsId = (ReceiverType->isObjCIdType() || 
+                          ReceiverType->isObjCQualifiedIdType());
+    if (receiverIsId || ReceiverType->isBlockPointerType() ||
         (Receiver && Context.isObjCNSObjectType(Receiver->getType()))) {
       Method = LookupInstanceMethodInGlobalPool(Sel, 
-                                              SourceRange(LBracLoc, RBracLoc));
+                                                SourceRange(LBracLoc, RBracLoc),
+                                                receiverIsId);
       if (!Method)
         Method = LookupFactoryMethodInGlobalPool(Sel, 
-                                               SourceRange(LBracLoc, RBracLoc));
+                                                 SourceRange(LBracLoc, RBracLoc),
+                                                 receiverIsId);
     } else if (ReceiverType->isObjCClassType() ||
                ReceiverType->isObjCQualifiedClassType()) {
       // Handle messages to Class.
@@ -891,12 +895,14 @@
         // If not messaging 'self', look for any factory method named 'Sel'.
         if (!Receiver || !isSelfExpr(Receiver)) {
           Method = LookupFactoryMethodInGlobalPool(Sel, 
-                                               SourceRange(LBracLoc, RBracLoc));
+                                               SourceRange(LBracLoc, RBracLoc),
+                                                   true);
           if (!Method) {
             // If no class (factory) method was found, check if an _instance_
             // method of the same name exists in the root class only.
             Method = LookupInstanceMethodInGlobalPool(Sel,
-                                               SourceRange(LBracLoc, RBracLoc));
+                                               SourceRange(LBracLoc, RBracLoc),
+                                                      true);
             if (Method)
                 if (const ObjCInterfaceDecl *ID =
                   dyn_cast<ObjCInterfaceDecl>(Method->getDeclContext())) {
@@ -951,7 +957,7 @@
             // compatibility. FIXME: should we deviate??
             if (OCIType->qual_empty()) {
               Method = LookupInstanceMethodInGlobalPool(Sel,
-                                                 SourceRange(LBracLoc, RBracLoc));
+                                                 SourceRange(LBracLoc, RBracLoc)); 
               if (Method && !OCIType->getInterfaceDecl()->isForwardDecl())
                 Diag(Loc, diag::warn_maynot_respond)
                   << OCIType->getInterfaceDecl()->getIdentifier() << Sel;