foo.c: In function 'main':
foo.c:42:8: warning: 'n1' may be used uninitialized [-Wmaybe-uninitialized]
   42 |     b2 =  m / n1;
      |     ~~~^~~~~~~~~
foo.c:28:13: note: 'n1' was declared here
   28 |     int m1, n1;
      |             ^~

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