foo.cc: In function 'int w(int*, int, int)':
foo.cc:20:1: warning: no return statement in function returning non-void [-Wreturn-type]
   20 | }
      | ^
foo.cc: In function 'int r(int*, int, int)':
foo.cc:27:1: warning: no return statement in function returning non-void [-Wreturn-type]
   27 | }
      | ^

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