foo.c: In function ‘is_prime’:
foo.c:25:5: error: expected expression at end of input
   25 |     if (num % 2 == 0)
      |     ^~
foo.c:25:5: note: ‘-Wmisleading-indentation’ is disabled from this point onwards, since column-tracking was disabled due to the size of the code/headers
foo.c:25:5: note: adding ‘-flarge-source-files’ will allow for more column-tracking support, at the expense of compilation time and memory
foo.c:25:5: error: expected declaration or statement at end of input
foo.c:27: warning: control reaches end of non-void function [-Wreturn-type]