7ffc3fbb2f
There are no widely deployed standard libraries providing sized deallocation functions, so we have to punt and ask the user if they want us to use sized deallocation. In the future, when such libraries are deployed, we can teach the driver to detect them and enable this feature. N3536 claimed that a weak thunk from sized to unsized deallocation could be emitted to avoid breaking backwards compatibility with standard libraries not providing sized deallocation. However, this approach and other variations don't work in practice. With the weak function approach, the thunk has to have default visibility in order to ensure that it is overridden by other DSOs providing sized deallocation. Weak, default visibility symbols are particularly expensive on MachO, so John McCall was considering disabling this feature by default on Darwin. It also changes behavior ELF linking behavior, causing certain otherwise unreferenced object files from an archive to be pulled into the link. Our second approach was to use an extern_weak function declaration and do an inline conditional branch at the deletion call site. This doesn't work because extern_weak only works on MachO if you have some archive providing the default value of the extern_weak symbol. Arranging to provide such an archive has the same challenges as providing the symbol in the standard library. Not to mention that extern_weak doesn't really work on COFF. Reviewers: rsmith, rjmccall Differential Revision: http://reviews.llvm.org/D8467 llvm-svn: 232788
166 lines
4.0 KiB
ReStructuredText
166 lines
4.0 KiB
ReStructuredText
=====================================
|
|
Clang 3.7 (In-Progress) Release Notes
|
|
=====================================
|
|
|
|
.. contents::
|
|
:local:
|
|
:depth: 2
|
|
|
|
Written by the `LLVM Team <http://llvm.org/>`_
|
|
|
|
.. warning::
|
|
|
|
These are in-progress notes for the upcoming Clang 3.7 release. You may
|
|
prefer the `Clang 3.5 Release Notes
|
|
<http://llvm.org/releases/3.5.0/tools/clang/docs/ReleaseNotes.html>`_.
|
|
|
|
Introduction
|
|
============
|
|
|
|
This document contains the release notes for the Clang C/C++/Objective-C
|
|
frontend, part of the LLVM Compiler Infrastructure, release 3.7. Here we
|
|
describe the status of Clang in some detail, including major
|
|
improvements from the previous release and new feature work. For the
|
|
general LLVM release notes, see `the LLVM
|
|
documentation <http://llvm.org/docs/ReleaseNotes.html>`_. All LLVM
|
|
releases may be downloaded from the `LLVM releases web
|
|
site <http://llvm.org/releases/>`_.
|
|
|
|
For more information about Clang or LLVM, including information about
|
|
the latest release, please check out the main please see the `Clang Web
|
|
Site <http://clang.llvm.org>`_ or the `LLVM Web
|
|
Site <http://llvm.org>`_.
|
|
|
|
Note that if you are reading this file from a Subversion checkout or the
|
|
main Clang web page, this document applies to the *next* release, not
|
|
the current one. To see the release notes for a specific release, please
|
|
see the `releases page <http://llvm.org/releases/>`_.
|
|
|
|
What's New in Clang 3.7?
|
|
========================
|
|
|
|
Some of the major new features and improvements to Clang are listed
|
|
here. Generic improvements to Clang as a whole or to its underlying
|
|
infrastructure are described first, followed by language-specific
|
|
sections with improvements to Clang's support for those languages.
|
|
|
|
Major New Features
|
|
------------------
|
|
|
|
- Feature ...
|
|
|
|
|
|
Improvements to Clang's diagnostics
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Clang's diagnostics are constantly being improved to catch more issues,
|
|
explain them more clearly, and provide more accurate source information
|
|
about them. The improvements since the 3.5 release include:
|
|
|
|
- ...
|
|
|
|
New Compiler Flags
|
|
------------------
|
|
|
|
The sized deallocation feature of C++14 is now controlled by the
|
|
``-fsized-deallocation`` flag. This feature relies on library support that
|
|
isn't yet widely deployed, so the user must supply an extra flag to get the
|
|
extra functionality.
|
|
|
|
The option ....
|
|
|
|
|
|
New Pragmas in Clang
|
|
-----------------------
|
|
|
|
Clang now supports the ...
|
|
|
|
Windows Support
|
|
---------------
|
|
|
|
Clang's support for building native Windows programs ...
|
|
|
|
|
|
C Language Changes in Clang
|
|
---------------------------
|
|
|
|
...
|
|
|
|
C11 Feature Support
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
...
|
|
|
|
C++ Language Changes in Clang
|
|
-----------------------------
|
|
|
|
- ...
|
|
|
|
C++11 Feature Support
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
...
|
|
|
|
Objective-C Language Changes in Clang
|
|
-------------------------------------
|
|
|
|
...
|
|
|
|
OpenCL C Language Changes in Clang
|
|
----------------------------------
|
|
|
|
...
|
|
|
|
Internal API Changes
|
|
--------------------
|
|
|
|
These are major API changes that have happened since the 3.6 release of
|
|
Clang. If upgrading an external codebase that uses Clang as a library,
|
|
this section should help get you past the largest hurdles of upgrading.
|
|
|
|
...
|
|
|
|
libclang
|
|
--------
|
|
|
|
...
|
|
|
|
Static Analyzer
|
|
---------------
|
|
|
|
...
|
|
|
|
Core Analysis Improvements
|
|
==========================
|
|
|
|
- ...
|
|
|
|
New Issues Found
|
|
================
|
|
|
|
- ...
|
|
|
|
Python Binding Changes
|
|
----------------------
|
|
|
|
The following methods have been added:
|
|
|
|
- ...
|
|
|
|
Significant Known Problems
|
|
==========================
|
|
|
|
Additional Information
|
|
======================
|
|
|
|
A wide variety of additional information is available on the `Clang web
|
|
page <http://clang.llvm.org/>`_. The web page contains versions of the
|
|
API documentation which are up-to-date with the Subversion version of
|
|
the source code. You can access versions of these documents specific to
|
|
this release by going into the "``clang/docs/``" directory in the Clang
|
|
tree.
|
|
|
|
If you have any questions or comments about Clang, please feel free to
|
|
contact us via the `mailing
|
|
list <http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev>`_.
|