tidy - cppcoreguidelines-avoid-non-const-global-variables — Extra Clang Tools 22.0.0git documentation (original) (raw)

Finds non-const global variables as described in I.2of C++ Core Guidelines. As R.6of C++ Core Guidelines is a duplicate of rule I.2it also covers that rule.

char a; // Warns! const char b = 0;

namespace some_namespace { char c; // Warns! const char d = 0; }

char * c_ptr1 = &some_namespace::c; // Warns! char *const c_const_ptr = &some_namespace::c; // Warns! char & c_reference = some_namespace::c; // Warns!

class Foo // No Warnings inside Foo, only namespace scope is covered { public: char e = 0; const char f = 0; protected: char g = 0; private: char h = 0; };

The variables a, c, c_ptr1, c_const_ptr and c_referencewill all generate warnings since they are either a non-const globally accessible variable, a pointer or a reference providing global access to non-const data or both.

Options¶

AllowInternalLinkage¶

When set to true, static non-const variables and variables in anonymous namespaces will not generate a warning. The default value is false.

AllowThreadLocal¶

When set to true, non-const global variables with thread-local storage duration will not generate a warning. The default value is false.