foo.c: In function 'main':
foo.c:6:9: warning: implicit declaration of function 'scan_f'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    6 |         scan_f("a=%d,b=%d",&a,&b);
      |         ^~~~~~
      |         scanf
/nix/store/jfkmqz20q8fsaqizcml86adxqyzlwllx-binutils-2.38/bin/ld: /tmp/ccDwQhre.o: in function `main':
foo.c:(.text.startup+0x16): undefined reference to `scan_f'
collect2: error: ld returned 1 exit status

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