A list of user-visible changes, in chronological order
Extensions moved to include/ext
.
Include files from the SGI/HP sources that pre-date the ISO standard
are added. These files are placed into
the include/backward
directory and a deprecated warning
is added that notifies on inclusion (-Wno-deprecated
deactivates the warning.)
Deprecated include backward/strstream
added.
Removal of include builtinbuf.h
, indstream.h
, parsestream.h
, PlotFile.h
, SFile.h
, stdiostream.h
, and stream.h
.
Extensions from SGI/HP moved from namespace std
to namespace __gnu_cxx
. As part of this, the following
new includes are
added: ext/algorithm
, ext/functional
, ext/iterator
, ext/memory
, and ext/numeric
.
Extensions to basic_filebuf
introduced: __gnu_cxx::enc_filebuf
, and __gnu_cxx::stdio_filebuf
.
Extensions to tree data structures added in ext/rb_tree
.
Removal of ext/tree
, moved to backward/tree.h
.
Symbol versioning introduced for shared library.
Removal of include backward/strstream.h
.
Allocator changes. Change __malloc_alloc
to malloc_allocator
and __new_alloc
to new_allocator
.
For GCC releases from 2.95 through the 3.1 series, defining
__USE_MALLOC
on the gcc command line would change the
default allocation strategy to instead use malloc
and
free
. For the 3.2 and 3.3 release series the same
functionality was spelled _GLIBCXX_FORCE_NEW
. From
GCC 3.4 onwards the functionality is enabled by setting
GLIBCXX_FORCE_NEW
in the environment, see
the mt allocator chapter
for details.
Error handling in iostreams cleaned up, made consistent.
Large file support.
Extensions for generic characters and char_traits
added in ext/pod_char_traits.h
.
Support for wchar_t
specializations of basic_filebuf
enhanced to support UTF-8
and Unicode
, depending on host. More hosts support basic wchar_t
functionality.
Support for char_traits
beyond builtin types.
Conformant allocator
class and usage in containers. As
part of this, the following extensions are
added: ext/bitmap_allocator.h
, ext/debug_allocator.h
, ext/mt_allocator.h
, ext/malloc_allocator.h
,ext/new_allocator.h
, ext/pool_allocator.h
.
This is a change from all previous versions, and may require
source-level changes due to allocator-related changes to structures
names and template parameters, filenames, and file locations. Some,
like __simple_alloc, __allocator, __alloc,
and
_Alloc_traits
have been removed.
Default behavior of std::allocator
has changed.
Previous versions prior to 3.4 cache allocations in a memory
pool, instead of passing through to call the global allocation
operators (i.e., __gnu_cxx::pool_allocator
). More
recent versions default to the
simpler __gnu_cxx::new_allocator
.
Previously, all allocators were written to the SGI
style, and all STL containers expected this interface. This
interface had a traits class called _Alloc_traits
that
attempted to provide more information for compile-time allocation
selection and optimization. This traits class had another allocator
wrapper, __simple_alloc<T,A>
, which was a
wrapper around another allocator, A, which itself is an allocator
for instances of T. But wait, there's more:
__allocator<T,A>
is another adapter. Many of
the provided allocator classes were SGI style: such classes can be
changed to a conforming interface with this wrapper:
__allocator<T, __alloc>
is thus the same as
allocator<T>
.
The class allocator
used the typedef
__alloc to select an underlying allocator that
satisfied memory allocation requests. The selection of this
underlying allocator was not user-configurable.
Table B.6. Extension Allocators
Allocator (3.4) | Header (3.4) | Allocator (3.[0-3]) | Header (3.[0-3]) |
---|---|---|---|
__gnu_cxx::new_allocator<T> | ext/new_allocator.h | std::__new_alloc | memory |
__gnu_cxx::malloc_allocator<T> | ext/malloc_allocator.h | std::__malloc_alloc_template<int> | memory |
__gnu_cxx::debug_allocator<T> | ext/debug_allocator.h | std::debug_alloc<T> | memory |
__gnu_cxx::__pool_alloc<T> | ext/pool_allocator.h | std::__default_alloc_template<bool,int> | memory |
__gnu_cxx::__mt_alloc<T> | ext/mt_allocator.h | ||
__gnu_cxx::bitmap_allocator<T> | ext/bitmap_allocator.h |
Releases after gcc-3.4 have continued to add to the collection of available allocators. All of these new allocators are standard-style. The following table includes details, along with the first released version of GCC that included the extension allocator.
Table B.7. Extension Allocators Continued
Allocator | Include | Version |
---|---|---|
__gnu_cxx::array_allocator<T> | ext/array_allocator.h | 4.0.0 |
__gnu_cxx::throw_allocator<T> | ext/throw_allocator.h | 4.2.0 |
Debug mode first appears.
Precompiled header support PCH support.
Macro guard for changed, from _GLIBCPP_
to _GLIBCXX_
.
Extension ext/stdio_sync_filebuf.h
added.
Extension ext/demangle.h
added.
TR1 features first appear.
Extension allocator ext/array_allocator.h
added.
Extension codecvt
specializations moved to ext/codecvt_specializations.h
.
Removal of ext/demangle.h
.
Removal of cassert
from all standard headers: now has to be explicitly included for std::assert
calls.
Extensions for policy-based data structures first added. New includes,
types, namespace pb_assoc
.
Extensions for typelists added in ext/typelist.h
.
Extension for policy-based basic_string
first added: __gnu_cxx::__versa_string
in ext/vstring.h
.
Default visibility attributes applied to namespace std
. Support for -fvisibility
.
TR1 random
, complex
, and C compatibility headers added.
Extensions for concurrent programming consolidated
into ext/concurrence.h
and ext/atomicity.h
,
including change of namespace to __gnu_cxx
in some
cases. Added types
include _Lock_policy
, __concurrence_lock_error
, __concurrence_unlock_error
, __mutex
, __scoped_lock
.
Extensions for type traits consolidated
into ext/type_traits.h
. Additional traits are added
(__conditional_type
, __enable_if
, others.)
Extensions for policy-based data structures revised. New includes,
types, namespace moved to __pb_ds
.
Extensions for debug mode modified: now nested in namespace
std::__debug
and extensions in namespace
__gnu_cxx::__debug
.
Extensions added: ext/typelist.h
and ext/throw_allocator.h
.
C++0X features first appear.
TR1 regex
and cmath
's mathematical special function added.
Backward include edit.
Removed
algobase.h
algo.h
alloc.h
bvector.h
complex.h
defalloc.h
deque.h
fstream.h
function.h
hash_map.h
hash_set.h
hashtable.h
heap.h
iomanip.h
iostream.h
istream.h
iterator.h
list.h
map.h
multimap.h
multiset.h
new.h
ostream.h
pair.h
queue.h
rope.h
set.h
slist.h
stack.h
streambuf.h
stream.h
tempbuf.h
tree.h
vector.h
Added
hash_map
and hash_set
Added in C++11
auto_ptr.h
and binders.h
Header dependency streamlining.
algorithm
no longer includes climits
, cstring
, or iosfwd
bitset
no longer includes istream
or ostream
, adds iosfwd
functional
no longer includes cstddef
iomanip
no longer includes istream
, istream
, or functional
, adds ioswd
numeric
no longer includes iterator
string
no longer includes algorithm
or memory
valarray
no longer includes numeric
or cstdlib
tr1/hashtable
no longer includes memory
or functional
tr1/memory
no longer includes algorithm
tr1/random
no longer includes algorithm
or fstream
Debug mode for unordered_map
and unordered_set
.
Parallel mode first appears.
Variadic template implementations of items in tuple
and
functional
.
Default what
implementations give more elaborate
exception strings for bad_cast
,
bad_typeid
, bad_exception
, and
bad_alloc
.
PCH binary files no longer installed. Instead, the source files are installed.
Namespace pb_ds moved to __gnu_pb_ds.
C++0X features.
Added.
atomic
,
chrono
,
condition_variable
,
forward_list
,
initializer_list
,
mutex
,
ratio
,
thread
Updated and improved.
algorithm
,
system_error
,
type_traits
Use of the GNU extension namespace association converted to inline namespaces.
Preliminary support for initializer_list
and defaulted and deleted constructors in container classes.
unique_ptr
.
Support for new character types char16_t
and char32_t added
to char_traits
, basic_string
, numeric_limits
,
and assorted compile-time type traits.
Support for string conversions to_string
and to_wstring
.
Member functions taking string arguments were added to iostreams
including basic_filebuf
, basic_ofstream
,
and basic_ifstream
.
Exception propagation support,
including exception_ptr
, current_exception
, copy_exception
,
and rethrow_exception
.
Uglification of try
to __try
and catch
to __catch
.
Audit of internal mutex usage, conversion to functions returning static local mutex.
Extensions
added: ext/pointer.h
and ext/extptr_allocator.h
. Support
for non-standard pointer types has been added
to vector
and forward_list
.
C++0X features.
Added.
functional
,
future
,
random
Updated and improved.
atomic
,
system_error
,
type_traits
Add support for explicit operators and standard layout types.
Profile mode first appears.
Support for decimal floating-point arithmetic, including decimal32
, decimal64
, and decimal128
.
Python pretty-printers are added for use with appropriately-advanced versions of gdb.
Audit for application of function attributes nothrow, const, pure, and noreturn.
The default behavior for comparing typeinfo names changed, so
in typeinfo
, __GXX_MERGED_TYPEINFO_NAMES
now defaults to zero.
Extensions modified: ext/throw_allocator.h
.
Use constexpr and nullptr where appropriate throughout the library.
The library was updated to avoid including
stddef.h
in order
to reduce namespace pollution.
Reference-count annotations to assist data race detectors.
Added make_exception_ptr
as an alias of
copy_exception
.
Use of noexcept throughout library.
Partial support for C++11 allocators first appears.
monotonic_clock
renamed to
steady_clock
as required by the final C++11
standard.
A new clocale model for newlib is available.
The library was updated to avoid including
unistd.h
in order
to reduce namespace pollution.
Debug Mode was improved for unordered containers.
New random number engines and distributions. Optimisations for random.
New --enable-libstdcxx-verbose configure option
The --enable-libstdcxx-time configure option becomes unnecessary given a sufficiently recent glibc.
Implementation of regex
completed.
C++14 library and TS implementations are added.
copy_exception
deprecated.
__gnu_cxx::array_allocator
deprecated.
ABI transition adds new implementations of several components, using the
abi_tag
attribute and the __cxx11
inline
namespace to distinguish the new entities from the old ones.
Use of the new or old ABI can be selected per-translation unit with the _GLIBCXX_USE_CXX11_ABI macro.
New non-reference-counted string
implementation.
New list
implementation containing a new
data member in order to provide O(1) size()
.
C++11 support completed (movable iostreams, new I/O manipulators,
Unicode conversion utilities, atomic operations for
shared_ptr
, functions for notifying condition
variables and making futures ready at thread exit).
Changed formatting of floating point types when
ios_base::fixed|ios_base::scientific
is set in a stream's
format flags.
Improved C++14 support and TS implementations.
New random number engines and distributions.
GDB Xmethods for containers and unique_ptr
added.
has_trivial_default_constructor
,
has_trivial_copy_constructor
and
has_trivial_copy_assign
deprecated.