objective-c: warn when autosynthesizing a property which has same
name as an existing ivar since this is common source of error
when people remove @synthesize to take advantage of autosynthesis.
// rdar://11671080
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158756 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 9ca078d..d27acf7 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -630,6 +630,9 @@
"auto property synthesis will not synthesize property"
" declared in a protocol">,
InGroup<DiagGroup<"objc-protocol-property-synthesis">>;
+def warn_autosynthesis_property_ivar_match :Warning<
+ "auto autosynthesized property has same name as an existing ivar">,
+ InGroup<DiagGroup<"objc-autosynthesis-property-ivar-name-match">>;
def warn_missing_explicit_synthesis : Warning <
"auto property synthesis is synthesizing property not explicitly synthesized">,
InGroup<DiagGroup<"objc-missing-property-synthesis">>, DefaultIgnore;
diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index 84dc9ca..20dbf58 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -755,6 +755,22 @@
}
if (!Ivar) {
+ if (AtLoc.isInvalid()) {
+ // Check when default synthesizing a property that there is
+ // an ivar matching property name and issue warning; since this
+ // is the most common case of not using an ivar used for backing
+ // property in non-default synthesis case.
+ ObjCInterfaceDecl *ClassDeclared=0;
+ ObjCIvarDecl *originalIvar =
+ IDecl->lookupInstanceVariable(property->getIdentifier(),
+ ClassDeclared);
+ if (originalIvar) {
+ Diag(PropertyDiagLoc,
+ diag::warn_autosynthesis_property_ivar_match);
+ Diag(property->getLocation(), diag::note_property_declare);
+ Diag(originalIvar->getLocation(), diag::note_ivar_decl);
+ }
+ }
// In ARC, give the ivar a lifetime qualifier based on the
// property attributes.
if (getLangOpts().ObjCAutoRefCount &&
diff --git a/test/SemaObjC/default-synthesize-2.m b/test/SemaObjC/default-synthesize-2.m
index b95f263..eeeab5f 100644
--- a/test/SemaObjC/default-synthesize-2.m
+++ b/test/SemaObjC/default-synthesize-2.m
@@ -41,12 +41,13 @@
// Test3
@interface Test3
{
- id uid;
+ id uid; // expected-note {{ivar is declared here}}
}
-@property (readwrite, assign) id uid;
+@property (readwrite, assign) id uid; // expected-note {{property declared here}}
@end
-@implementation Test3
+// rdar://11671080
+@implementation Test3 // expected-warning {{auto autosynthesized property has same name as an existing ivar}}
// Oops, forgot to write @synthesize! will be default synthesized
- (void) myMethod {
self.uid = 0; // Use of the “setter”
