Clean up the analysis of the collection operand to ObjC
for-in statements; specifically, make sure to close over any
temporaries or cleanups it might require. In ARC, this has
implications for the lifetime of the collection, so emit it
with a retain and release it upon exit from the loop.
rdar://problem/9817306
llvm-svn: 136204
diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index c22555e..0fd3f03 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -965,6 +965,76 @@
return Owned(static_cast<Stmt*>(Result.get()));
}
+ExprResult
+Sema::ActOnObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
+ assert(collection);
+
+ // Bail out early if we've got a type-dependent expression.
+ if (collection->isTypeDependent()) return Owned(collection);
+
+ // Perform normal l-value conversion.
+ ExprResult result = DefaultFunctionArrayLvalueConversion(collection);
+ if (result.isInvalid())
+ return ExprError();
+ collection = result.take();
+
+ // The operand needs to have object-pointer type.
+ // TODO: should we do a contextual conversion?
+ const ObjCObjectPointerType *pointerType =
+ collection->getType()->getAs<ObjCObjectPointerType>();
+ if (!pointerType)
+ return Diag(forLoc, diag::err_collection_expr_type)
+ << collection->getType() << collection->getSourceRange();
+
+ // Check that the operand provides
+ // - countByEnumeratingWithState:objects:count:
+ const ObjCObjectType *objectType = pointerType->getObjectType();
+ ObjCInterfaceDecl *iface = objectType->getInterface();
+
+ // If we have a forward-declared type, we can't do this check.
+ if (iface && iface->isForwardDecl()) {
+ // This is ill-formed under ARC.
+ if (getLangOptions().ObjCAutoRefCount) {
+ Diag(forLoc, diag::err_arc_collection_forward)
+ << pointerType->getPointeeType() << collection->getSourceRange();
+ }
+
+ // Otherwise, if we have any useful type information, check that
+ // the type declares the appropriate method.
+ } else if (iface || !objectType->qual_empty()) {
+ IdentifierInfo *selectorIdents[] = {
+ &Context.Idents.get("countByEnumeratingWithState"),
+ &Context.Idents.get("objects"),
+ &Context.Idents.get("count")
+ };
+ Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]);
+
+ ObjCMethodDecl *method = 0;
+
+ // If there's an interface, look in both the public and private APIs.
+ if (iface) {
+ method = iface->lookupInstanceMethod(selector);
+ if (!method) method = LookupPrivateInstanceMethod(selector, iface);
+ }
+
+ // Also check protocol qualifiers.
+ if (!method)
+ method = LookupMethodInQualifiedType(selector, pointerType,
+ /*instance*/ true);
+
+ // If we didn't find it anywhere, give up.
+ if (!method) {
+ Diag(forLoc, diag::warn_collection_expr_type)
+ << collection->getType() << selector << collection->getSourceRange();
+ }
+
+ // TODO: check for an incompatible signature?
+ }
+
+ // Wrap up any cleanups in the expression.
+ return Owned(MaybeCreateExprWithCleanups(collection));
+}
+
StmtResult
Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
SourceLocation LParenLoc,
@@ -1000,38 +1070,7 @@
Diag(ForLoc, diag::err_selector_element_type)
<< FirstType << First->getSourceRange();
}
- if (Second && !Second->isTypeDependent()) {
- ExprResult Result = DefaultFunctionArrayLvalueConversion(Second);
- if (Result.isInvalid())
- return StmtError();
- Second = Result.take();
- QualType SecondType = Second->getType();
- if (!SecondType->isObjCObjectPointerType())
- Diag(ForLoc, diag::err_collection_expr_type)
- << SecondType << Second->getSourceRange();
- else if (const ObjCObjectPointerType *OPT =
- SecondType->getAsObjCInterfacePointerType()) {
- SmallVector<IdentifierInfo *, 4> KeyIdents;
- IdentifierInfo* selIdent =
- &Context.Idents.get("countByEnumeratingWithState");
- KeyIdents.push_back(selIdent);
- selIdent = &Context.Idents.get("objects");
- KeyIdents.push_back(selIdent);
- selIdent = &Context.Idents.get("count");
- KeyIdents.push_back(selIdent);
- Selector CSelector = Context.Selectors.getSelector(3, &KeyIdents[0]);
- if (ObjCInterfaceDecl *IDecl = OPT->getInterfaceDecl()) {
- if (!IDecl->isForwardDecl() &&
- !IDecl->lookupInstanceMethod(CSelector) &&
- !LookupMethodInQualifiedType(CSelector, OPT, true)) {
- // Must further look into private implementation methods.
- if (!LookupPrivateInstanceMethod(CSelector, IDecl))
- Diag(ForLoc, diag::warn_collection_expr_type)
- << SecondType << CSelector << Second->getSourceRange();
- }
- }
- }
- }
+
return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body,
ForLoc, RParenLoc));
}