From 3256fe5912706c3f04089cf981c12bc9b4caf6c3 Mon Sep 17 00:00:00 2001
From: Aaron Ballman <aaron@aaronballman.com>
Date: Wed, 19 Feb 2014 20:39:48 +0000
Subject: [PATCH] Moving the documentation for the availability attribute into
AttrDocs.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@201712 91177308-0d34-0410-b5e6-96231b3b80d8
---
docs/LanguageExtensions.rst | 97 -------------------------------
include/clang/Basic/Attr.td | 2 +-
include/clang/Basic/AttrDocs.td | 100 +++++++++++++++++++++++++++++++-
3 files changed, 100 insertions(+), 99 deletions(-)
diff --git a/docs/LanguageExtensions.rst b/docs/LanguageExtensions.rst
index e7a38053af8..25ed9f8610f 100644
--- a/docs/LanguageExtensions.rst
+++ b/docs/LanguageExtensions.rst
@@ -426,103 +426,6 @@ should be treated as a system framework, regardless of how it was found in the
framework search path. For consistency, we recommend that such files never be
included in installed versions of the framework.
-Availability attribute
-======================
-
-Clang introduces the ``availability`` attribute, which can be placed on
-declarations to describe the lifecycle of that declaration relative to
-operating system versions. Consider the function declaration for a
-hypothetical function ``f``:
-
-.. code-block:: c++
-
- void f(void) __attribute__((availability(macosx,introduced=10.4,deprecated=10.6,obsoleted=10.7)));
-
-The availability attribute states that ``f`` was introduced in Mac OS X 10.4,
-deprecated in Mac OS X 10.6, and obsoleted in Mac OS X 10.7. This information
-is used by Clang to determine when it is safe to use ``f``: for example, if
-Clang is instructed to compile code for Mac OS X 10.5, a call to ``f()``
-succeeds. If Clang is instructed to compile code for Mac OS X 10.6, the call
-succeeds but Clang emits a warning specifying that the function is deprecated.
-Finally, if Clang is instructed to compile code for Mac OS X 10.7, the call
-fails because ``f()`` is no longer available.
-
-The availability attribute is a comma-separated list starting with the
-platform name and then including clauses specifying important milestones in the
-declaration's lifetime (in any order) along with additional information. Those
-clauses can be:
-
-introduced=\ *version*
- The first version in which this declaration was introduced.
-
-deprecated=\ *version*
- The first version in which this declaration was deprecated, meaning that
- users should migrate away from this API.
-
-obsoleted=\ *version*
- The first version in which this declaration was obsoleted, meaning that it
- was removed completely and can no longer be used.
-
-unavailable
- This declaration is never available on this platform.
-
-message=\ *string-literal*
- Additional message text that Clang will provide when emitting a warning or
- error about use of a deprecated or obsoleted declaration. Useful to direct
- users to replacement APIs.
-
-Multiple availability attributes can be placed on a declaration, which may
-correspond to different platforms. Only the availability attribute with the
-platform corresponding to the target platform will be used; any others will be
-ignored. If no availability attribute specifies availability for the current
-target platform, the availability attributes are ignored. Supported platforms
-are:
-
-``ios``
- Apple's iOS operating system. The minimum deployment target is specified by
- the ``-mios-version-min=*version*`` or ``-miphoneos-version-min=*version*``
- command-line arguments.
-
-``macosx``
- Apple's Mac OS X operating system. The minimum deployment target is
- specified by the ``-mmacosx-version-min=*version*`` command-line argument.
-
-A declaration can be used even when deploying back to a platform version prior
-to when the declaration was introduced. When this happens, the declaration is
-`weakly linked
-<https://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/BPFrameworks/Concepts/WeakLinking.html>`_,
-as if the ``weak_import`` attribute were added to the declaration. A
-weakly-linked declaration may or may not be present a run-time, and a program
-can determine whether the declaration is present by checking whether the
-address of that declaration is non-NULL.
-
-If there are multiple declarations of the same entity, the availability
-attributes must either match on a per-platform basis or later
-declarations must not have availability attributes for that
-platform. For example:
-
-.. code-block:: c
-
- void g(void) __attribute__((availability(macosx,introduced=10.4)));
- void g(void) __attribute__((availability(macosx,introduced=10.4))); // okay, matches
- void g(void) __attribute__((availability(ios,introduced=4.0))); // okay, adds a new platform
- void g(void); // okay, inherits both macosx and ios availability from above.
- void g(void) __attribute__((availability(macosx,introduced=10.5))); // error: mismatch
-
-When one method overrides another, the overriding method can be more widely available than the overridden method, e.g.,:
-
-.. code-block:: objc
-
- @interface A
- - (id)method __attribute__((availability(macosx,introduced=10.4)));
- - (id)method2 __attribute__((availability(macosx,introduced=10.4)));
- @end
-
- @interface B : A
- - (id)method __attribute__((availability(macosx,introduced=10.3))); // okay: method moved into base class later
- - (id)method __attribute__((availability(macosx,introduced=10.5))); // error: this method was available via the base class in 10.4
- @end
-
Checks for Standard Language Features
=====================================
diff --git a/include/clang/Basic/Attr.td b/include/clang/Basic/Attr.td
index 5d66f316c37..cd8d8a9bdf3 100644
--- a/include/clang/Basic/Attr.td
+++ b/include/clang/Basic/Attr.td
@@ -413,7 +413,7 @@ def Availability : InheritableAttr {
let HasCustomParsing = 1;
let DuplicatesAllowedWhileMerging = 1;
// let Subjects = SubjectList<[Named]>;
- let Documentation = [Undocumented];
+ let Documentation = [AvailabilityDocs];
}
def Blocks : InheritableAttr {
diff --git a/include/clang/Basic/AttrDocs.td b/include/clang/Basic/AttrDocs.td
index 5340be42a80..37b61fdc228 100644
--- a/include/clang/Basic/AttrDocs.td
+++ b/include/clang/Basic/AttrDocs.td
@@ -311,4 +311,102 @@ implementation of an override in a subclass does not call super. For example:
- (void) AnnotMeth{};
^
}];
-}
\ No newline at end of file
+}
+
+def AvailabilityDocs : Documentation {
+ let Category = DocCatFunction;
+ let Content = [{
+The ``availability`` attribute can be placed on declarations to describe the
+lifecycle of that declaration relative to operating system versions. Consider
+the function declaration for a hypothetical function ``f``:
+
+.. code-block:: c++
+
+ void f(void) __attribute__((availability(macosx,introduced=10.4,deprecated=10.6,obsoleted=10.7)));
+
+The availability attribute states that ``f`` was introduced in Mac OS X 10.4,
+deprecated in Mac OS X 10.6, and obsoleted in Mac OS X 10.7. This information
+is used by Clang to determine when it is safe to use ``f``: for example, if
+Clang is instructed to compile code for Mac OS X 10.5, a call to ``f()``
+succeeds. If Clang is instructed to compile code for Mac OS X 10.6, the call
+succeeds but Clang emits a warning specifying that the function is deprecated.
+Finally, if Clang is instructed to compile code for Mac OS X 10.7, the call
+fails because ``f()`` is no longer available.
+
+The availability attribute is a comma-separated list starting with the
+platform name and then including clauses specifying important milestones in the
+declaration's lifetime (in any order) along with additional information. Those
+clauses can be:
+
+introduced=\ *version*
+ The first version in which this declaration was introduced.
+
+deprecated=\ *version*
+ The first version in which this declaration was deprecated, meaning that
+ users should migrate away from this API.
+
+obsoleted=\ *version*
+ The first version in which this declaration was obsoleted, meaning that it
+ was removed completely and can no longer be used.
+
+unavailable
+ This declaration is never available on this platform.
+
+message=\ *string-literal*
+ Additional message text that Clang will provide when emitting a warning or
+ error about use of a deprecated or obsoleted declaration. Useful to direct
+ users to replacement APIs.
+
+Multiple availability attributes can be placed on a declaration, which may
+correspond to different platforms. Only the availability attribute with the
+platform corresponding to the target platform will be used; any others will be
+ignored. If no availability attribute specifies availability for the current
+target platform, the availability attributes are ignored. Supported platforms
+are:
+
+``ios``
+ Apple's iOS operating system. The minimum deployment target is specified by
+ the ``-mios-version-min=*version*`` or ``-miphoneos-version-min=*version*``
+ command-line arguments.
+
+``macosx``
+ Apple's Mac OS X operating system. The minimum deployment target is
+ specified by the ``-mmacosx-version-min=*version*`` command-line argument.
+
+A declaration can be used even when deploying back to a platform version prior
+to when the declaration was introduced. When this happens, the declaration is
+`weakly linked
+<https://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/BPFrameworks/Concepts/WeakLinking.html>`_,
+as if the ``weak_import`` attribute were added to the declaration. A
+weakly-linked declaration may or may not be present a run-time, and a program
+can determine whether the declaration is present by checking whether the
+address of that declaration is non-NULL.
+
+If there are multiple declarations of the same entity, the availability
+attributes must either match on a per-platform basis or later
+declarations must not have availability attributes for that
+platform. For example:
+
+.. code-block:: c
+
+ void g(void) __attribute__((availability(macosx,introduced=10.4)));
+ void g(void) __attribute__((availability(macosx,introduced=10.4))); // okay, matches
+ void g(void) __attribute__((availability(ios,introduced=4.0))); // okay, adds a new platform
+ void g(void); // okay, inherits both macosx and ios availability from above.
+ void g(void) __attribute__((availability(macosx,introduced=10.5))); // error: mismatch
+
+When one method overrides another, the overriding method can be more widely available than the overridden method, e.g.,:
+
+.. code-block:: objc
+
+ @interface A
+ - (id)method __attribute__((availability(macosx,introduced=10.4)));
+ - (id)method2 __attribute__((availability(macosx,introduced=10.4)));
+ @end
+
+ @interface B : A
+ - (id)method __attribute__((availability(macosx,introduced=10.3))); // okay: method moved into base class later
+ - (id)method __attribute__((availability(macosx,introduced=10.5))); // error: this method was available via the base class in 10.4
+ @end
+ }];
+}
--
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