No type checking in ctype builtins

[Andrea Monaco via Gcc]

This program

  #include <ctype.h>

  int main ()
  {
    char *s;
    isspace (s);
  }

compiles with no warning in gcc 8.3.0, even though there's a type
mistake; the correct call would be isspace (*s).

The ctype functions are implemented as macros in glibc, so you can't
have type checking.  But they are also provided as builtins by gcc, so I
wonder why type checking is not performed in that case, either.



Thanks,

Andrea Monaco