foo.cc: In function 'int main()':
foo.cc:11:2: error: 'memset' was not declared in this scope
  memset(f, 0, sizeof(f));
  ^~~~~~
foo.cc:11:2: note: suggested alternative: 'wmemset'
  memset(f, 0, sizeof(f));
  ^~~~~~
  wmemset

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