[clang-tidy] Broken diagnostic for performance-avoid-endl

[VReichelt]

When I run clang-tidy -checks='-*,performance-avoid-endl' on the following code

#include <iostream>

#define COUT_ENDL std::cout << std::endl

void foo()
{
  COUT_ENDL;
}

I get the message

bug.cc:7:3: warning: do not use '' with streams; use '\n' instead [performance-avoid-endl]
   11 |   COUT_ENDL;
      |   ^
bug.cc:3:32: note: expanded from macro 'COUT_ENDL'
    7 | #define COUT_ENDL std::cout << std::endl
      |                                ^

which is slightly broken (note the empty '' in the first line).