/in/foo.c: In function 'test_for_P1772':
/in/foo.c:24:5: warning: implicit declaration of function '_itoa_s' [-Wimplicit-function-declaration]
     _itoa_s(i, num1, 4, 10);
     ^~~~~~~
/tmp/ccUyzCi1.o: In function `test_for_P1772':
foo.c:(.text+0xd5): undefined reference to `_itoa_s'
foo.c:(.text+0xee): undefined reference to `_itoa_s'
foo.c:(.text+0x106): undefined reference to `_itoa_s'
collect2: error: ld returned 1 exit status