Sema::CheckCompareOperands() and ASTContext::mergeTypes(): Change handling of ObjC qualified id types to be consistent with gcc. This changes a handful of test case errors into warnings (diff will tell you which cases have changed).

llvm-svn: 57841

4 files changed, 33 insertions, 8 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index deb80900bb3..f4266fb90d1 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -2036,14 +2036,30 @@ QualType ASTContext::mergeTypes(QualType LHS, QualType RHS) {
   if (LHSClass != RHSClass) {
     // ID is compatible with all qualified id types.
     if (LHS->isObjCQualifiedIdType()) {
-      if (const PointerType *PT = RHS->getAsPointerType())
-        if (isObjCIdType(PT->getPointeeType()))
+      if (const PointerType *PT = RHS->getAsPointerType()) {
+        QualType pType = PT->getPointeeType();
+        if (isObjCIdType(pType))
           return LHS;
+        // FIXME: need to use ObjCQualifiedIdTypesAreCompatible(LHS, RHS, true).
+        // Unfortunately, this API is part of Sema (which we don't have access
+        // to. Need to refactor. The following check is insufficient, since we 
+        // need to make sure the class implements the protocol.
+        if (pType->isObjCInterfaceType())
+          return LHS;
+      }
     }
     if (RHS->isObjCQualifiedIdType()) {
-      if (const PointerType *PT = LHS->getAsPointerType())
-        if (isObjCIdType(PT->getPointeeType()))
+      if (const PointerType *PT = LHS->getAsPointerType()) {
+        QualType pType = PT->getPointeeType();
+        if (isObjCIdType(pType))
           return RHS;
+        // FIXME: need to use ObjCQualifiedIdTypesAreCompatible(LHS, RHS, true).
+        // Unfortunately, this API is part of Sema (which we don't have access
+        // to. Need to refactor. The following check is insufficient, since we 
+        // need to make sure the class implements the protocol.
+        if (pType->isObjCInterfaceType())
+          return RHS;
+      }
     }
 
     // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 563718ccc8d..1f885165cd9 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -2061,6 +2061,13 @@ QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation loc,
   }
 
   if ((lType->isObjCQualifiedIdType() || rType->isObjCQualifiedIdType())) {
+    if ((lType->isPointerType() || rType->isPointerType()) &&
+        !Context.typesAreCompatible(lType, rType)) {
+      Diag(loc, diag::ext_typecheck_comparison_of_distinct_pointers,
+           lType.getAsString(), rType.getAsString(),
+           lex->getSourceRange(), rex->getSourceRange());
+      return QualType();
+    }
     if (ObjCQualifiedIdTypesAreCompatible(lType, rType, true)) {
       ImpCastExprToType(rex, lType);
       return Context.IntTy;
diff --git a/clang/test/SemaObjC/comptypes-1.m b/clang/test/SemaObjC/comptypes-1.m
index ec0e3805211..f6cd3a266b9 100644
--- a/clang/test/SemaObjC/comptypes-1.m
+++ b/clang/test/SemaObjC/comptypes-1.m
@@ -66,6 +66,8 @@ int main()
 
   /* Any comparison between 'MyClass *' and anything which is not an 'id'
      must generate a warning.  */
+  /* FIXME: GCC considers this a warning ("comparison of distinct pointer types"). */
+  /* There is a corresponding FIXME in ASTContext::mergeTypes() */
   if (obj_p == obj_c) foo() ; // expected-error {{invalid operands to binary expression ('id<MyProtocol>' and 'MyClass *')}}
 
   if (obj_c == obj_cp) foo() ; // expected-warning {{comparison of distinct pointer types ('MyClass *' and 'MyOtherClass *')}} 
@@ -80,8 +82,8 @@ int main()
   if (obj_p == obj_cp) foo() ; /* Ok */
 
 
-  if (obj_p == obj_C) foo() ; // expected-error {{invalid operands to binary expression ('id<MyProtocol>' and 'Class')}} 
-  if (obj_C == obj_p) foo() ; // expected-error {{invalid operands to binary expression ('Class' and 'id<MyProtocol>')}} 
+  if (obj_p == obj_C) foo() ; // expected-warning {{comparison of distinct pointer types ('id<MyProtocol>' and 'Class')}} 
+  if (obj_C == obj_p) foo() ; // expected-warning {{comparison of distinct pointer types ('Class' and 'id<MyProtocol>')}} 
   if (obj_cp == obj_C) foo() ; // expected-warning {{comparison of distinct pointer types ('MyOtherClass *' and 'Class')}} 
   if (obj_C == obj_cp) foo() ; // expected-warning {{comparison of distinct pointer types ('Class' and 'MyOtherClass *')}}
 
diff --git a/clang/test/SemaObjC/comptypes-7.m b/clang/test/SemaObjC/comptypes-7.m
index ce0391ea07a..27b832b7369 100644
--- a/clang/test/SemaObjC/comptypes-7.m
+++ b/clang/test/SemaObjC/comptypes-7.m
@@ -58,8 +58,8 @@ int main()
 
   if (obj_p == i) foo() ; // expected-warning {{comparison between pointer and integer ('id<MyProtocol>' and 'int')}}
   if (i == obj_p) foo() ; // expected-warning {{comparison between pointer and integer ('int' and 'id<MyProtocol>')}}
-  if (obj_p == j) foo() ; // expected-error {{invalid operands to binary expression ('id<MyProtocol>' and 'int *')}}
-  if (j == obj_p) foo() ; // expected-error {{invalid operands to binary expression ('int *' and 'id<MyProtocol>')}}
+  if (obj_p == j) foo() ; // expected-warning {{comparison of distinct pointer types ('id<MyProtocol>' and 'int *')}}
+  if (j == obj_p) foo() ; // expected-warning {{comparison of distinct pointer types ('int *' and 'id<MyProtocol>')}}
 
   if (obj_C == i) foo() ; // expected-warning {{comparison between pointer and integer ('Class' and 'int')}}
   if (i == obj_C) foo() ; // expected-warning {{comparison between pointer and integer ('int' and 'Class')}}