foo.cc: In function 'int main()':
foo.cc:23:3: error: 'memcpy' was not declared in this scope
   memcpy(b, a, sizeof a);
   ^~~~~~
foo.cc:23:3: note: suggested alternative: 'wmemcpy'
   memcpy(b, a, sizeof a);
   ^~~~~~
   wmemcpy

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