V2018. Cast should not remove 'const' qualifier from the type that is pointed to by a pointer or a reference.

This diagnostic rule was added at users' request.

The analyzer has detected a situation where the 'const' qualifier was removed. Modifying an object, which was declared with the 'const' qualifier, through a pointer/reference to non-'const' type leads to undefined behavior. Besides, such code often indicates poor application design.

Look at the example:

void read_settings(const char *buf);
const char* get_settings_file_name();
bool settings_present();
// ....
void init_settings()
{
  const char name[MAX_PATH] = "default.cfg";
  if (settings_present())
  {
    strcpy((char *)name, get_settings_file_name());
  }
  read_settings(name);
}

To avoid undefined behavior, abandon constancy when declaring a local variable:

void read_settings(const char *buf);
const char* get_settings_file_name();
bool settings_present();
// ....
void init_settings()
{
  char name[MAX_PATH] = "default.cfg";
  if (settings_present())
  {
    strcpy(name, get_settings_file_name());
  }
  read_settings(name);
}

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