18c2ecf20Sopenharmony_ci.. include:: ../disclaimer-zh_CN.rst 28c2ecf20Sopenharmony_ci 38c2ecf20Sopenharmony_ci:Original: :ref:`Documentation/process/programming-language.rst <programming_language>` 48c2ecf20Sopenharmony_ci:Translator: Alex Shi <alex.shi@linux.alibaba.com> 58c2ecf20Sopenharmony_ci 68c2ecf20Sopenharmony_ci.. _cn_programming_language: 78c2ecf20Sopenharmony_ci 88c2ecf20Sopenharmony_ci程序设计语言 98c2ecf20Sopenharmony_ci============ 108c2ecf20Sopenharmony_ci 118c2ecf20Sopenharmony_ci内核是用C语言 :ref:`c-language <cn_c-language>` 编写的。更准确地说,内核通常是用 :ref:`gcc <cn_gcc>` 128c2ecf20Sopenharmony_ci在 ``-std=gnu89`` :ref:`gcc-c-dialect-options <cn_gcc-c-dialect-options>` 下编译的:ISO C90的 GNU 方言( 138c2ecf20Sopenharmony_ci包括一些C99特性) 148c2ecf20Sopenharmony_ci 158c2ecf20Sopenharmony_ci这种方言包含对语言 :ref:`gnu-extensions <cn_gnu-extensions>` 的许多扩展,当然,它们许多都在内核中使用。 168c2ecf20Sopenharmony_ci 178c2ecf20Sopenharmony_ci对于一些体系结构,有一些使用 :ref:`clang <cn_clang>` 和 :ref:`icc <cn_icc>` 编译内核 188c2ecf20Sopenharmony_ci的支持,尽管在编写此文档时还没有完成,仍需要第三方补丁。 198c2ecf20Sopenharmony_ci 208c2ecf20Sopenharmony_ci属性 218c2ecf20Sopenharmony_ci---- 228c2ecf20Sopenharmony_ci 238c2ecf20Sopenharmony_ci在整个内核中使用的一个常见扩展是属性(attributes) :ref:`gcc-attribute-syntax <cn_gcc-attribute-syntax>` 248c2ecf20Sopenharmony_ci属性允许将实现定义的语义引入语言实体(如变量、函数或类型),而无需对语言进行 258c2ecf20Sopenharmony_ci重大的语法更改(例如添加新关键字) :ref:`n2049 <cn_n2049>` 268c2ecf20Sopenharmony_ci 278c2ecf20Sopenharmony_ci在某些情况下,属性是可选的(即不支持这些属性的编译器仍然应该生成正确的代码, 288c2ecf20Sopenharmony_ci即使其速度较慢或执行的编译时检查/诊断次数不够) 298c2ecf20Sopenharmony_ci 308c2ecf20Sopenharmony_ci内核定义了伪关键字(例如, ``pure`` ),而不是直接使用GNU属性语法(例如, 318c2ecf20Sopenharmony_ci``__attribute__((__pure__))`` ),以检测可以使用哪些关键字和/或缩短代码, 具体 328c2ecf20Sopenharmony_ci请参阅 ``include/linux/compiler_attributes.h`` 338c2ecf20Sopenharmony_ci 348c2ecf20Sopenharmony_ci.. _cn_c-language: 358c2ecf20Sopenharmony_ci 368c2ecf20Sopenharmony_cic-language 378c2ecf20Sopenharmony_ci http://www.open-std.org/jtc1/sc22/wg14/www/standards 388c2ecf20Sopenharmony_ci 398c2ecf20Sopenharmony_ci.. _cn_gcc: 408c2ecf20Sopenharmony_ci 418c2ecf20Sopenharmony_cigcc 428c2ecf20Sopenharmony_ci https://gcc.gnu.org 438c2ecf20Sopenharmony_ci 448c2ecf20Sopenharmony_ci.. _cn_clang: 458c2ecf20Sopenharmony_ci 468c2ecf20Sopenharmony_ciclang 478c2ecf20Sopenharmony_ci https://clang.llvm.org 488c2ecf20Sopenharmony_ci 498c2ecf20Sopenharmony_ci.. _cn_icc: 508c2ecf20Sopenharmony_ci 518c2ecf20Sopenharmony_ciicc 528c2ecf20Sopenharmony_ci https://software.intel.com/en-us/c-compilers 538c2ecf20Sopenharmony_ci 548c2ecf20Sopenharmony_ci.. _cn_gcc-c-dialect-options: 558c2ecf20Sopenharmony_ci 568c2ecf20Sopenharmony_cic-dialect-options 578c2ecf20Sopenharmony_ci https://gcc.gnu.org/onlinedocs/gcc/C-Dialect-Options.html 588c2ecf20Sopenharmony_ci 598c2ecf20Sopenharmony_ci.. _cn_gnu-extensions: 608c2ecf20Sopenharmony_ci 618c2ecf20Sopenharmony_cignu-extensions 628c2ecf20Sopenharmony_ci https://gcc.gnu.org/onlinedocs/gcc/C-Extensions.html 638c2ecf20Sopenharmony_ci 648c2ecf20Sopenharmony_ci.. _cn_gcc-attribute-syntax: 658c2ecf20Sopenharmony_ci 668c2ecf20Sopenharmony_cigcc-attribute-syntax 678c2ecf20Sopenharmony_ci https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html 688c2ecf20Sopenharmony_ci 698c2ecf20Sopenharmony_ci.. _cn_n2049: 708c2ecf20Sopenharmony_ci 718c2ecf20Sopenharmony_cin2049 728c2ecf20Sopenharmony_ci http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2049.pdf 73