Make ABSL_ATTRIBUTE_VIEW and ABSL_ATTRIBUTE_OWNER public
Deprecates ABSL_INTERNAL_ATTRIBUTE_VIEW and ABSL_INTERNAL_ATTRIBUTE_OWNER
PiperOrigin-RevId: 665523780
Change-Id: Ic4f7e3083a7db9d8fd057d3e002b81c775a4a87e
diff --git a/absl/base/attributes.h b/absl/base/attributes.h
index c5f35be..ab96f1a 100644
--- a/absl/base/attributes.h
+++ b/absl/base/attributes.h
@@ -829,31 +829,56 @@
#define ABSL_ATTRIBUTE_LIFETIME_BOUND
#endif
-// ABSL_INTERNAL_ATTRIBUTE_VIEW indicates that a type acts like a view i.e. a
-// raw (non-owning) pointer. This enables diagnoses similar to those enabled by
-// ABSL_ATTRIBUTE_LIFETIME_BOUND.
+// ABSL_ATTRIBUTE_VIEW indicates that a type is solely a "view" of data that it
+// points to, similarly to a span, string_view, or other non-owning reference
+// type.
+// This enables diagnosing certain lifetime issues similar to those enabled by
+// ABSL_ATTRIBUTE_LIFETIME_BOUND, such as:
+//
+// struct ABSL_ATTRIBUTE_VIEW StringView {
+// template<class R>
+// StringView(const R&);
+// };
+//
+// StringView f(std::string s) {
+// return s; // warning: address of stack memory returned
+// }
//
// See the following links for details:
// https://reviews.llvm.org/D64448
// https://lists.llvm.org/pipermail/cfe-dev/2018-November/060355.html
#if ABSL_HAVE_CPP_ATTRIBUTE(gsl::Pointer)
-#define ABSL_INTERNAL_ATTRIBUTE_VIEW [[gsl::Pointer]]
+#define ABSL_ATTRIBUTE_VIEW [[gsl::Pointer]]
#else
-#define ABSL_INTERNAL_ATTRIBUTE_VIEW
+#define ABSL_ATTRIBUTE_VIEW
#endif
+#define ABSL_INTERNAL_ATTRIBUTE_VIEW ABSL_ATTRIBUTE_VIEW // Deprecated
-// ABSL_INTERNAL_ATTRIBUTE_OWNER indicates that a type acts like a smart
-// (owning) pointer. This enables diagnoses similar to those enabled by
-// ABSL_ATTRIBUTE_LIFETIME_BOUND.
+// ABSL_ATTRIBUTE_OWNER indicates that a type is a container, smart pointer, or
+// similar class that owns all the data that it points to.
+// This enables diagnosing certain lifetime issues similar to those enabled by
+// ABSL_ATTRIBUTE_LIFETIME_BOUND, such as:
+//
+// struct ABSL_ATTRIBUTE_VIEW StringView {
+// template<class R>
+// StringView(const R&);
+// };
+//
+// struct ABSL_ATTRIBUTE_OWNER String {};
+//
+// StringView f(String s) {
+// return s; // warning: address of stack memory returned
+// }
//
// See the following links for details:
// https://reviews.llvm.org/D64448
// https://lists.llvm.org/pipermail/cfe-dev/2018-November/060355.html
#if ABSL_HAVE_CPP_ATTRIBUTE(gsl::Owner)
-#define ABSL_INTERNAL_ATTRIBUTE_OWNER [[gsl::Owner]]
+#define ABSL_ATTRIBUTE_OWNER [[gsl::Owner]]
#else
-#define ABSL_INTERNAL_ATTRIBUTE_OWNER
+#define ABSL_ATTRIBUTE_OWNER
#endif
+#define ABSL_INTERNAL_ATTRIBUTE_OWNER ABSL_ATTRIBUTE_OWNER // Deprecated
// ABSL_ATTRIBUTE_TRIVIAL_ABI
// Indicates that a type is "trivially relocatable" -- meaning it can be
