C++0x is the working name of the next ISO C++ standard, due by the end of this decade, which introduces a host of new features into the standard C++ language and library. This project seeks to implement new C++0x features in GCC and to make it one of the first compilers to bring C++0x to C++ programmers.
C++0x features are available as part of the "mainline" GCC
compiler in the trunk of
GCC's Subversion
repository and in GCC 4.3 and later. To enable C++0x
support, add the command-line parameter -std=c++0x
to your g++
command line. Or, to enable GNU
extensions in addition to C++0x extensions,
add -std=gnu++0x
to your g++
command
line.
Important: because the ISO C++0x draft is still evolving, GCC's support for C++0x is experimental. No attempt will be made to maintain backward compatibility with implementations of C++0x features that do not reflect the final C++0x standard.
The following table lists new language features that have been accepted into the C++0x draft standard. The "Proposal" column provides a link to the ISO C++ committee proposal that describes the feature, while the "Available in GCC?" column indicates the first version of GCC that contains an implementation of this feature (if it has been implemented). For the most complete and up-to-date information about new language features in C++0x, please see the ISO C++ Committee Papers and look for the most recent "State of C++ Evolution" paper by Alisdair Meridith.
For information about C++0x support in a specific version of GCC, please see:
Language Feature | Proposal | Available in GCC? |
---|---|---|
Rvalue references | N2118 | GCC 4.3 |
Rvalue references for *this |
N2439 | No |
Initialization of class objects by rvalues | N1610 | Yes |
Non-static data member initializers | N2756 | No |
Variadic templates | N2242 | GCC 4.3 |
Extending variadic template template parameters | N2555 | GCC 4.4 |
Initializer lists | N2672 | GCC 4.4 |
Static assertions | N1720 | GCC 4.3 |
auto -typed variables |
N1984 | GCC 4.4 |
Multi-declarator auto |
N1737 | GCC 4.4 |
Removal of auto as a storage-class specifier | N2546 | GCC 4.4 |
New function declarator syntax | N2541 | GCC 4.4 |
New wording for C++0x lambdas | N2927 | GCC 4.5 |
Declared type of an expression | N2343 | GCC 4.3 |
Right angle brackets | N1757 | GCC 4.3 |
Default template arguments for function templates | DR226 | GCC 4.3 |
Solving the SFINAE problem for expressions | DR339 | GCC 4.4 |
Template aliases | N2258 | No |
Extern templates | N1987 | Yes |
Null pointer constant | N2431 | GCC 4.6 |
Strongly-typed enums | N2347 | GCC 4.4 |
Forward declarations for enums | N2764 | No |
Generalized attributes | N2761 | No |
Generalized constant expressions | N2235 | No [Branch] |
Alignment support | N2341 | No |
Delegating constructors | N1986 | No [Patch] |
Inheriting constructors | N2540 | No |
Explicit conversion operators | N2437 | GCC 4.5 |
New character types | N2249 | GCC 4.4 |
Unicode string literals | N2442 | GCC 4.5 |
Raw string literals | N2442 | GCC 4.5 |
Universal character name literals | N2170 | GCC 4.5 |
Extensible literals | N2765 | No |
Standard Layout Types | N2342 | GCC 4.5 |
Defaulted and deleted functions | N2346 | GCC 4.4 |
Extended friend declarations | N1791 | No |
Extending sizeof |
N2253 | GCC 4.4 |
Inline namespaces | N2535 | GCC 4.4 |
Unrestricted unions | N2544 | GCC 4.6 |
Local and unnamed types as template arguments | N2657 | GCC 4.5 |
Range-based for | N2930 | No |
Explicit virtual overrides | N2928 | No |
Minimal support for garbage collection and reachability-based leak detection | N2670 | No |
Allowing move constructors to throw [noexcept] | N3050 | GCC 4.6 (core language only) |
Defining move special member functions | N3053 | GCC 4.6 |
Concepts [no longer part of C++0x] | N2773 | Some development [Branch] |
Concurrency | ||
Sequence points | N2239 | No |
Atomic operations | N2427 | GCC 4.4 |
Strong Compare and Exchange | N2748 | No |
Bidirectional Fences | N2752 | No |
Memory model | N2429 | No |
Data-dependency ordering: atomics and memory model | N2664 | No |
Propagating exceptions | N2179 | GCC 4.4 |
Abandoning a process and at_quick_exit | N2440 | No |
Allow atomics use in signal handlers | N2547 | No |
Thread-local storage | N2659 | No |
Dynamic initialization and destruction with concurrency | N2660 | No |
C99 Features in C++0x | ||
__func__ predefined identifier |
N2340 | GCC 4.3 |
C99 preprocessor | N1653 | GCC 4.3 |
long long |
N1811 | GCC 4.3 |
Extended integral types | N1988 | No |
The status of the library implementation can be tracked in this table
Significant work has been done on the constexpr feature of C++0x.
The sources can be found on the constexpr
branch in the
GCC git mirror. If you
are interested in helping, you can send patches to the gcc-patches
mailing list as usual (preferably with "c++0x constexpr" in the subject
line), or send a pull request to [email protected].
Support for
the Concepts
feature, which is no longer part of C++0x, is not under active development
at this time. The prototype implementation,
ConceptGCC,
can be found on the branches/conceptgcc-branch
. Previously
there was a plan to develop a superior implementation on a separate
development branch, branches/cxx0x-concepts-branch
, but not much
work was done on that branch.
Please send FSF & GNU inquiries & questions to [email protected]. There are also other ways to contact the FSF.
These pages are maintained by the GCC team.
For questions related to the use of GCC, please consult these web pages and the GCC manuals. If that fails, the [email protected] mailing list might help.Copyright (C) Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA.
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Last modified 2010-07-14 |