foo.c: In function 'main':
foo.c:6:9: warning: passing argument 1 of 'printf' makes pointer from integer without a cast [-Wint-conversion]
    6 |  printf('1')
      |         ^~~
      |         |
      |         int
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:105:32: note: expected 'const char * restrict' but argument is of type 'int'
  105 | printf (const char *__restrict __fmt, ...)
      |         ~~~~~~~~~~~~~~~~~~~~~~~^~~~~
foo.c:6:2: warning: format not a string literal and no format arguments [-Wformat-security]
    6 |  printf('1')
      |  ^~~~~~
foo.c:6:13: error: expected ';' before '}' token
    6 |  printf('1')
      |             ^
      |             ;
    7 | }
      | ~            

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