Add Support for 'warn_unused_result" attribute on
objective-c methods. (radar 7418262).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99903 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 154d319..58c40cf 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -783,8 +783,9 @@
def warn_attribute_ignored : Warning<"%0 attribute ignored">;
def warn_attribute_precede_definition : Warning<
"attribute declaration must precede definition">;
-def warn_attribute_void_function : Warning<
- "attribute %0 cannot be applied to functions without return value">;
+def warn_attribute_void_function_method : Warning<
+ "attribute %0 cannot be applied to "
+ "%select{functions|Objective-C method}1 without return value">;
def warn_attribute_weak_on_field : Warning<
"__weak attribute cannot be specified on a field declaration">;
def warn_attribute_weak_on_local : Warning<
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 6a71e92..b4e5a5d 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -914,8 +914,15 @@
case CXXConstructExprClass:
return false;
- case ObjCMessageExprClass:
+ case ObjCMessageExprClass: {
+ const ObjCMessageExpr *ME = cast<ObjCMessageExpr>(this);
+ const ObjCMethodDecl *MD = ME->getMethodDecl();
+ if (MD && MD->getAttr<WarnUnusedResultAttr>()) {
+ Loc = getExprLoc();
+ return true;
+ }
return false;
+ }
case ObjCImplicitSetterGetterRefExprClass: { // Dot syntax for message send.
#if 0
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index b304112..d12dec4 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -837,18 +837,24 @@
return;
}
- if (!isFunction(D)) {
+ if (!isFunction(D) && !isa<ObjCMethodDecl>(D)) {
S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
<< Attr.getName() << 0 /*function*/;
return;
}
- if (getFunctionType(D)->getResultType()->isVoidType()) {
- S.Diag(Attr.getLoc(), diag::warn_attribute_void_function)
- << Attr.getName();
+ if (isFunction(D) && getFunctionType(D)->getResultType()->isVoidType()) {
+ S.Diag(Attr.getLoc(), diag::warn_attribute_void_function_method)
+ << Attr.getName() << 0;
return;
}
-
+ if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
+ if (MD->getResultType()->isVoidType()) {
+ S.Diag(Attr.getLoc(), diag::warn_attribute_void_function_method)
+ << Attr.getName() << 1;
+ return;
+ }
+
D->addAttr(::new (S.Context) WarnUnusedResultAttr());
}
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 733022a..1e37bb0 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -119,7 +119,13 @@
}
}
}
-
+ else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
+ const ObjCMethodDecl *MD = ME->getMethodDecl();
+ if (MD && MD->getAttr<WarnUnusedResultAttr>()) {
+ Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result";
+ return;
+ }
+ }
Diag(Loc, DiagID) << R1 << R2;
}
diff --git a/test/SemaObjC/method-warn-unused-attribute.m b/test/SemaObjC/method-warn-unused-attribute.m
index d9dcf99..042f442 100644
--- a/test/SemaObjC/method-warn-unused-attribute.m
+++ b/test/SemaObjC/method-warn-unused-attribute.m
@@ -1,8 +1,16 @@
// RUN: %clang_cc1 -fsyntax-only -Wunused-value -verify %s
@interface INTF
-// Currently this is rejected by both GCC and Clang (and Clang was crashing on it).
-- (id) foo __attribute__((warn_unused_result)); // expected-warning{{warning: 'warn_unused_result' attribute only applies to function types}}
+- (id) foo __attribute__((warn_unused_result));
+- (void) garf __attribute__((warn_unused_result)); // expected-warning {{attribute 'warn_unused_result' cannot be applied to Objective-C method without return value}}
+- (int) fee __attribute__((warn_unused_result));
++ (int) c __attribute__((warn_unused_result));
@end
+void foo(INTF *a) {
+ [a garf];
+ [a fee]; // expected-warning {{ignoring return value of function declared with warn_unused_result attribute}}
+ [INTF c]; // expected-warning {{ignoring return value of function declared with warn_unused_result attribute}}
+}
+