主流编译器对C++11的支持分析
更新时间:2013/3/21 点击:4609次
GCC 4.8刚刚发布,Clang 3.3也发布在即,如果你使用Visual Studio 2012,也可以通过安装一个实验性的CTP更新(VS2012 Nov CTP)来获取额外的C++11支持;除此之外,这里还比较了Intel C++编译器v.13.0,不过这仍然是一个预览版。
特性 | VS2012 Nov CTP | g++ 4.8 | Clang 3.3 | Intel 13.0 |
---|---|---|---|---|
auto | Yes | Yes | Yes | Yes |
decltype | Yes | Yes | Yes | Yes |
Rvalue references and move semantics | Yes | Yes | Yes | Yes |
Lambda expressions | Yes | Yes | Yes | Yes |
nullptr | Yes | Yes | Yes | Yes |
static_assert | Yes | Yes | Yes | Yes |
Range based for loop | Yes | Yes | Yes | Yes |
Trailing return type in functions | Yes | Yes | Yes | Yes |
extern templates | Yes | Yes | Yes | Yes |
>> for nested templates | Yes | Yes | Yes | Yes |
Local and unnamed types as template arguments | Yes | Yes | Yes | Yes |
Variadic macros | Yes | Yes | Yes | Yes |
Variadic templates | Yes | Yes | Yes | Yes |
Default template arguments in function templates | Yes | Yes | Yes | Yes |
final method keyword | Yes | Yes | Yes | No |
override method keyword | Yes | Yes | Yes | No |
Strongly typed enums | Yes | Yes | Yes | Partial |
Forward declared enums | Yes | Yes | Yes | Partial |
Initializer lists | Yes | Yes | Yes | Partial |
explicit type conversion operators | Yes | Yes | Yes | No |
Raw string literals | Yes | Yes | Yes | No |
Forwarding constructors | Yes | Yes | Yes | No |
Template aliases | No | Yes | Yes | Yes |
Defaulted methods | No | Yes | Yes | Yes |
Deleted methods | No | Yes | Yes | Yes |
New built-in types | Partial | Yes | Yes | Partial |
Alignment support | Partial | Yes | Yes | No |
Inline namespaces | No | Yes | Yes | No |
sizeof on non-static data members without an instance | No | Yes | Yes | No |
Changed restrictions on union members | No | Yes | Yes | No |
User defined literals | No | Yes | Yes | No |
Encoding support in literals | No | Yes | Yes | No |
Arbitrary expressions in template deduction contexts | No | Yes | Yes | Don’t know |
Non-static data member initializers | No | Yes | Yes | Don’t know |
noexcept | No | Yes | Yes | Partial |
constexpr | No | Yes | Yes | Partial |
C99 compatibility | Partial | Yes | Partial | Yes |
Generalized attributes | No | Yes | Partial | Yes |
Thread local storage | Partial | Yes | No | Partial |
Inheriting constructors | No | Yes | No | No |
Rvalue references for *this | No | No | Yes | No |
Minimal support for garbage collection | Yes | No | No | Don’t know |
从表格数据我们可以看到,GCC正在取代Clang成为C++11支持最佳的编译器,而Visual Studio在对C++11特性的支持上也有明显的改进,特别是新增对variadic templates、 initializer lists以及raw literals的支持。当然这些支持中那些属于完全支持,哪些是无bug的支持不得而知,需要开发者自己去体验。
除了C++11特性之外,对其类库的支持同样需要的到重视,但下表中不会标注各编译器支持与标准库之间的细小差别。
- 微软的库并没有实现那些需要尚未被实现的语言功能支持的东西,例如 constexpr(在Visual Studio 2012最初的发行版中)。库文件并没有为支持2012年11月CTP中使用的特性——如 initializer list(初始化列表)和variadic template(可变参数模板)——而更新。
- GCC libstdc++有点滞后,因为它不支持正则表达式以及低级并行特性,此外,在很多情况下也没有实现constexpr方法。
- Clang对libc++的支持在Mac OS上非常完美,但部分功能尚未在Windows和Linux下实现。
特性 | MSVC | libstdc++ | libc++ |
---|---|---|---|
Concurrency: async/future/promise/packaged_task | Yes | Yes | Yes |
Concurrency: thread and related | Yes | Yes | Yes |
Concurrency: condition variables | Yes | Yes | Yes |
Concurrency: mutexes | Yes | Yes | Yes |
Concurrency: atomic types and operations | Yes | Yes | Yes |
Concurrency: relaxed memory ordering and fences | Yes | No | Yes |
Smart pointers | Yes | Yes | Yes |
Tuples | Yes | Yes | Yes |
std::bind | Yes | Yes | Yes |
std::function | Yes | Yes | Yes |
Regular expressions | Yes | No | Yes |
Type traits | Yes | Partial | Yes |
std::forward_list | Yes | Yes | Yes |
std::array | Yes | Yes | Yes |
Hash tables | Yes | Yes | Yes |
Random number generation | Yes | Yes | Yes |
Compile time rational numbers (ratio) | Yes | Yes | Yes |
Time utilities (chrono) | Yes | Yes | Yes |
Initializer lists | Yes | Yes | Yes |
Diagnostics (system_error) | Yes | Yes | Yes |
STL refinements and new algorithms | Yes | Yes | Yes |
General purpose (move, forward, declval etc.) | Yes | Yes | Yes |
可以看到,C++及其类库的支持已经大有提升,Clang和GCC几乎已经为C++11提供了完整的支持;Visual Studio也增强了对C++11的支持;同时Intel的编译器对C++11的支持大幅提升。
相信到明年,各主流编译器应该都能够完全支持C++11标准。