[attributes] Add an attribute os_consumes_this, with similar semantics to ns_consumes_self
The attribute specifies that the call of the C++ method consumes a
reference to "this".
Differential Revision: https://reviews.llvm.org/D55155
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index d644040..04125e6 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -90,6 +90,10 @@
[{!S->isBitField()}],
"non-bit-field non-static data members">;
+def NonStaticCXXMethod : SubsetSubject<CXXMethod,
+ [{!S->isStatic()}],
+ "non-static member functions">;
+
def NonStaticNonConstCXXMethod
: SubsetSubject<CXXMethod,
[{!S->isStatic() && !S->isConst()}],
@@ -846,6 +850,12 @@
let Documentation = [RetainBehaviorDocs];
}
+def OSConsumesThis : InheritableAttr {
+ let Spellings = [Clang<"os_consumes_this">];
+ let Subjects = SubjectList<[NonStaticCXXMethod]>;
+ let Documentation = [RetainBehaviorDocs];
+}
+
def Cleanup : InheritableAttr {
let Spellings = [GCC<"cleanup">];
let Args = [FunctionArgument<"FunctionDecl">];
@@ -1649,13 +1659,13 @@
def NSConsumesSelf : InheritableAttr {
let Spellings = [Clang<"ns_consumes_self">];
let Subjects = SubjectList<[ObjCMethod]>;
- let Documentation = [Undocumented];
+ let Documentation = [RetainBehaviorDocs];
}
def NSConsumed : InheritableParamAttr {
let Spellings = [Clang<"ns_consumed">];
let Subjects = SubjectList<[ParmVar]>;
- let Documentation = [Undocumented];
+ let Documentation = [RetainBehaviorDocs];
}
def ObjCException : InheritableAttr {
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index 5c9f2b9..e72ef25 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -862,6 +862,9 @@
Similiarly, the annotation ``__attribute__((ns_returns_not_retained))``
specifies that the object is returned at ``+0`` and the ownership remains with
the callee.
+The annotation ``__attribute__((ns_consumes_self))`` specifies that
+the Objective-C method call consumes the reference to ``self``, e.g. by
+attaching it to a supplied parameter.
Additionally, parameters can have an annotation
``__attribute__((ns_consumed))``, which specifies that passing an owned object
as that parameter effectively transfers the ownership, and the caller is no
@@ -881,7 +884,11 @@
``__attribute__((os_returns_not_retained))``,
``__attribute__((os_returns_retained))`` and ``__attribute__((os_consumed))``,
with the same respective semantics.
-These attributes are also used by the Clang Static Analyzer.
+Similar to ``__attribute__((ns_consumes_self))``,
+``__attribute__((os_consumes_this))`` specifies that the method call consumes
+the reference to "this" (e.g., when attaching it to a different object supplied
+as a parameter).
+These attributes are only used by the Clang Static Analyzer.
The family of attributes ``X_returns_X_retained`` can be added to functions,
C++ methods, and Objective-C methods and properties.
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index a2520c0..78374b8 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -6408,6 +6408,9 @@
case ParsedAttr::AT_NSConsumesSelf:
handleSimpleAttribute<NSConsumesSelfAttr>(S, D, AL);
break;
+ case ParsedAttr::AT_OSConsumesThis:
+ handleSimpleAttribute<OSConsumesThisAttr>(S, D, AL);
+ break;
case ParsedAttr::AT_NSReturnsAutoreleased:
case ParsedAttr::AT_NSReturnsNotRetained:
case ParsedAttr::AT_NSReturnsRetained:
diff --git a/clang/test/Sema/attr-osobject.cpp b/clang/test/Sema/attr-osobject.cpp
index fe9ed6b..8d87453 100644
--- a/clang/test/Sema/attr-osobject.cpp
+++ b/clang/test/Sema/attr-osobject.cpp
@@ -4,6 +4,10 @@
__attribute__((os_returns_retained)) S* method_returns_retained() {
return nullptr;
}
+
+ __attribute__((os_consumes_this)) void method_consumes_this();
+
+ __attribute__((os_consumes_this)) static void rejected_on_static(); // expected-warning{{'os_consumes_this' attribute only applies to non-static member functions}}
};
__attribute__((os_returns_retained)) S *ret_retained() {
return nullptr;
@@ -37,6 +41,8 @@
__attribute__((os_returns_not_retained(10))) S* os_returns_no_retained_no_extra_args( S *arg) { // expected-error{{'os_returns_not_retained' attribute takes no arguments}}
return nullptr;
-}
+}
struct __attribute__((os_returns_not_retained)) NoNotRetainedAttrOnStruct {}; // expected-warning{{'os_returns_not_retained' attribute only applies to functions, Objective-C methods, and Objective-C properties}}
+
+__attribute__((os_consumes_this)) void no_consumes_this_on_function() {} // expected-warning{{'os_consumes_this' attribute only applies to non-static member functions}}
