foo.c: In function 'main':
foo.c:7:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    7 |         gets(s);
      |         ^~~~
In file included from foo.c:1:
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.c:10:9: warning: 'sum' may be used uninitialized [-Wmaybe-uninitialized]
   10 |         printf("%d",sum);
      |         ^~~~~~~~~~~~~~~~
foo.c:4:13: note: 'sum' was declared here
    4 |         int sum;
      |             ^~~
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/ccGp5KMS.o: in function `main':
foo.c:(.text.startup+0xc): warning: the `gets' function is dangerous and should not be used.

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