foo.c: In function 'main':
foo.c:6:2: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    6 |  scanf_s("%d", &a);
      |  ^~~~~~~
      |  scanf
foo.c:26:2: warning: 'f' may be used uninitialized [-Wmaybe-uninitialized]
   26 |  printf("%d", f);
      |  ^~~~~~~~~~~~~~~
foo.c:11:6: note: 'f' was declared here
   11 |  int f;
      |      ^
/nix/store/j2gmfdd29cp3rcvghmn1a5kgcnmf8myp-binutils-2.40/bin/ld: /tmp/ccTcLoDe.o: in function `main':
foo.c:(.text.startup+0x12): undefined reference to `scanf_s'
collect2: error: ld returned 1 exit status

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