# S6936: Names of well-known C standard library macros and functions should not be used as identifiers
id: no-stdlib-name-as-id
name: Standard Library Names Should Not Be Shadowed
severity: error
category: maintainability
defect_class: correctness
inline_tier: blocking
language: c

message: "{{NAME}} is a well-known C standard library name and should not be used as an identifier"

description: |
  Shadowing standard library names (malloc, free, printf, etc.) causes
  confusion and can lead to subtle bugs when macros or headers are included.

  ✅ FIX: Rename to something descriptive

  ```c
  int my_allocator = 10;  // GOOD
  ```

query: |
  [
    (declaration
      (init_declarator
        (identifier) @NAME))
    (parameter_declaration
      (identifier) @NAME)
    (function_declarator
      (identifier) @NAME)
  ]

metavars:
  - NAME

post_filter: c_stdlib_name

tags:
  - maintainability
  - c
  - bad-practice
  - readability

examples:
  bad: |
    int malloc = 10;    // BAD - shadows stdlib function
    int printf = 20;    // BAD

  good: |
    int my_size = 10;   // GOOD

has_fix: true
fix_action: rename_identifier