foo.cc:10:5: error: redefinition of 'int main()'
   10 | int main()
      |     ^~~~
foo.cc:3:5: note: 'int main()' previously defined here
    3 | int main()
      |     ^~~~
foo.cc:17:5: error: redefinition of 'int main()'
   17 | int main()
      |     ^~~~
foo.cc:3:5: note: 'int main()' previously defined here
    3 | int main()
      |     ^~~~
foo.cc:24:5: error: redefinition of 'int main()'
   24 | int main()
      |     ^~~~
foo.cc:3:5: note: 'int main()' previously defined here
    3 | int main()
      |     ^~~~
foo.cc:31:5: error: redefinition of 'int main()'
   31 | int main()
      |     ^~~~
foo.cc:3:5: note: 'int main()' previously defined here
    3 | int main()
      |     ^~~~

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