foo.c: In function 'main':
foo.c:5:12: warning: character constant too long for its type
     printf('"enjoy yourself"\n');
            ^~~~~~~~~~~~~~~~~~~~
foo.c:5:12: warning: passing argument 1 of 'printf' makes pointer from integer without a cast [-Wint-conversion]
In file included from /usr/include/stdio.h:862:0,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:102:1: note: expected 'const char * restrict' but argument is of type 'int'
 printf (const char *__restrict __fmt, ...)
 ^~~~~~
foo.c:5:5: warning: format not a string literal and no format arguments [-Wformat-security]
     printf('"enjoy yourself"\n');
     ^~~~~~

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