Poor Style: Variable Never Used

C/C++
Solidity

Abstract

从未使用过该变量。

Explanation

从未使用过该变量。有可能该变量只是一个残留的无用代码，但也可能该未使用的变量会指出一个 bug。

示例 1：在以下代码中，复制粘贴错误导致同一个循环迭代器 (i) 使用了两次，而变量 j 却从未使用。


  int i,j;

  for (i=0; i < outer; i++) {
    for (i=0; i < inner; i++) {
      ...

References

[1] Standards Mapping - Common Weakness Enumeration CWE ID 563

[2] Standards Mapping - Motor Industry Software Reliability Association (MISRA) C Guidelines 2023 Rule 2.8

[3] Standards Mapping - Motor Industry Software Reliability Association (MISRA) C++ Guidelines 2008 Rule 0-1-3

[4] Standards Mapping - Motor Industry Software Reliability Association (MISRA) C++ Guidelines 2023 Rule 0.1.2, Rule 0.2.1, Rule 0.2.2, Rule 0.2.3, Rule 0.2.4

[5] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3050 CAT II

[6] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3050 CAT II

[7] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3050 CAT II

[8] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3050 CAT II

[9] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3050 CAT II

[10] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3050 CAT II

[11] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3050 CAT II

[12] Standards Mapping - Smart Contract Weakness Classification SWC-131

desc.structural.cpp.poor_style_variable_never_used