C11通过匿名的typedef结构？ [英] C11 anonymous structs via typedefs?

问题描述

匿名结构已在C11标准被添加，因此

Anonymous structs have been added in the C11 standard, so

typedef struct { 
    struct {int a, b};
    int c; 
} abc_struct;

是啥标准。是不是也很到位完整结构声明来使用typedef在标准范围内？例如：

is valid and standard. Is it also within the standard to use a typedef in place of the full struct declaration? E.g.:

typedef struct { 
    int a, b;
} ab_struct;

typedef struct { 
    ab_struct;
    int c; 
} abc_struct;

GCC的文件说，这是一个计划9延伸，但随后在工作
我试过几个编译器（包括GCC ...）。我的标准本身的阅读，
我认为这是好的，但这是那种近距离阅读，很容易搞砸了。

The GCC documentation says that this is a Plan 9 extension, but then it works in the few compilers I've tried (including GCC...). By my reading of the standard itself, I think it's OK, but this is the sort of close reading that's easy to screw up.

推荐答案

这显然是要求由的gcc约瑟夫·迈尔斯团队的问题到C委员会。和答案是否定的，它不是在C11有效

This was apparently asked in a question to the C committee by Joseph S. Myers of the gcc team. And the answer is no, it is not valid in C11.

在这里看到答案：

<一个href=\"http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1549.pdf\">http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1549.pdf

和迈尔斯的评论：

本周的伦敦WG14会议同意禁止使用的typedef的声明匿名结构和联合的字段，如每N1549。

This week's London WG14 meeting agreed to disallow the use of typedefs in declaring anonymous structure and union fields, as per N1549.

源<一个href=\"http://gcc.gnu.org/ml/gcc-patches/2011-03/msg01151.html\">http://gcc.gnu.org/ml/gcc-patches/2011-03/msg01151.html

有人问在SC22WG15.12205看到的 5.28 SC22WG14.12205，匿名结构（N1425）的在<一个href=\"http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1490.pdf\">http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1490.pdf

The question was asked in SC22WG15.12205 see 5.28 SC22WG14.12205, Anonymous Structures (N1425) in http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1490.pdf

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