foo.c: In function 'main':
foo.c:8:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    8 |     gets(a);
      |     ^~~~
In file included from foo.c:1:
/nix/store/rffag931pvbdiabwwa539wnwg1piqpx0-glibc-2.35-163-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: /tmp/ccO9f6pW.o: in function `main':
foo.c:(.text.startup+0x2b): warning: the `gets' function is dangerous and should not be used.

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