modernize-avoid-c-arrays

cppcoreguidelines-avoid-c-arrays redirects here as an alias for this check.

hicpp-avoid-c-arrays redirects here as an alias for this check.

Finds C-style array types and recommend to use std::array<> / std::vector<>. All types of C arrays are diagnosed.

However, fix-it are potentially dangerous in header files and are therefore not emitted right now.

int a[] = {1, 2}; // warning: do not declare C-style arrays, use std::array<> instead

int b[1]; // warning: do not declare C-style arrays, use std::array<> instead

void foo() {
  int c[b[0]]; // warning: do not declare C VLA arrays, use std::vector<> instead
}

template <typename T, int Size>
class array {
  T d[Size]; // warning: do not declare C-style arrays, use std::array<> instead

  int e[1]; // warning: do not declare C-style arrays, use std::array<> instead
};

array<int[4], 2> d; // warning: do not declare C-style arrays, use std::array<> instead

using k = int[4]; // warning: do not declare C-style arrays, use std::array<> instead

However, the extern "C" code is ignored, since it is common to share such headers between C code, and C++ code.

// Some header
extern "C" {

int f[] = {1, 2}; // not diagnosed

int j[1]; // not diagnosed

inline void bar() {
  {
    int j[j[0]]; // not diagnosed
  }
}

}

Similarly, the main() function is ignored. Its second and third parameters can be either char* argv[] or char** argv, but cannot be std::array<>.