Clang Formating of variables works unexpectedly

Clang Formating of variables works unexpectedly, highlighting similar uses of variable with different colors

void test() {
  QString s;

  #define m1(x)  #x
  #define m2(x)  m1(x)

  QString s1(s);
  QString s2(m1(s));
  QString s3(m2(s));
}

is highlighted as

but everything is as expected if clang plugin is turned off