MISRA C:2012 Rule 18.5

Declarations should contain no more than two levels of pointer nesting

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描述

规则定义

Declarations should contain no more than two levels of pointer nesting 1 .

理由

使用超过两级的指针嵌套会严重降低理解代码行为的能力。应避免这种用法。

故障排除

如果您预期会出现违规，但未看到该违规，请参阅诊断为何编码规范违规未按预期显示。

示例

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typedef char *INTPTR;

void function(char ** arrPar[ ])    /* Non-compliant - 3 levels */
{
    char   **  obj2;            /* Compliant */
    char   *** obj3;            /* Non-compliant */
    INTPTR *   obj4;            /* Compliant */
    INTPTR * const * const obj5;    /* Non-compliant */
    char   ** arr[10];            /* Compliant */
    char   ** (*parr)[10];        /* Compliant */
    char   *  (**pparr)[10];        /* Compliant */
}

struct s{
    char *   s1;                /* Compliant */
    char **  s2;                /* Compliant */
    char *** s3;                /* Non-compliant */
};

struct s *   ps1;            /* Compliant */
struct s **  ps2;            /* Compliant */
struct s *** ps3;            /* Non-compliant */       

char **  (  *pfunc1)(void);        /* Compliant */
char **  ( **pfunc2)(void);        /* Compliant */
char **  (***pfunc3)(void);        /* Non-compliant */
char *** ( **pfunc4)(void);        /* Non-compliant */

此示例展示了各种指针声明及其嵌套层级。嵌套层级超过两级的任何指针都被视为不合规。

检查信息

组：指针和数组
类别：建议
AGC 类别：可读性

另请参阅

主题

1 All MISRA coding rules and directives are © Copyright The MISRA Consortium Limited 2021.

The MISRA coding standards referenced in the Polyspace® Bug Finder™ documentation are from the following MISRA standards:

  • MISRA C:2004

  • MISRA C:2012

  • MISRA C:2023

  • MISRA C++:2008

  • MISRA C++:2023

MISRA and MISRA C are registered trademarks of The MISRA Consortium Limited 2021.