clang-tidy readability-identifier-naming for GCC's naming convention

clang-tidy-readability-identifier-naming-gcc.yml

CheckOptions:
  - key:             readability-identifier-naming.ClassCase
    value:           lower_case
  - key:             readability-identifier-naming.ClassMemberCase
    value:           lower_case
  - key:             readability-identifier-naming.ClassMemberPrefix
    value:           s_
  - key:             readability-identifier-naming.EnumCase
    value:           lower_case
  - key:             readability-identifier-naming.EnumConstantCase
    value:           lower_case
  - key:             readability-identifier-naming.FunctionCase
    value:           lower_case
  - key:             readability-identifier-naming.GlobalConstantCase
    value:           lower_case
  - key:             readability-identifier-naming.MacroDefinitionCase
    value:           aNy_CasE   # use either UPPER_CASE or lower_case depending on the context
  - key:             readability-identifier-naming.MemberCase
    value:           lower_case
  - key:             readability-identifier-naming.MemberPrefix
    value:           m_
  - key:             readability-identifier-naming.NamespaceCase
    value:           aNy_CasE
  - key:             readability-identifier-naming.ParameterCase
    value:           lower_case
  - key:             readability-identifier-naming.StaticConstantCase
    value:           lower_case
  - key:             readability-identifier-naming.StaticVariableCase
    value:           lower_case
  - key:             readability-identifier-naming.TemplateParameterCase
    value:           CamelCase
  - key:             readability-identifier-naming.TypeAliasCase
    value:           lower_case
  - key:             readability-identifier-naming.TypedefCase
    value:           lower_case
  - key:             readability-identifier-naming.VariableCase
    value:           lower_case
  - key:             readability-identifier-naming.IgnoreMainLikeFunctions
    value:           1

GCC states that

Macros names should be in ALL_CAPS when it's important to be aware that it's a macro (e.g. accessors and simple predicates), but in lowercase (e.g., size_int) where the macro is a wrapper for efficiency that should be considered as a function...

So macros can be in either UPPER_CASE or lower_case depending on the context.

" - key: eadability-identifier-naming.FunctionCase" have a typo

@HTuanPhong Thanks for pointing that out. Fixed it now