/in/foo.cc: In function 'int main()':
/in/foo.cc:13:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=0;i<10;i++)
  ^~~
/in/foo.cc:15:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   p=t[w1];t[w1]=t[w2];t[w2]=p;
   ^
/in/foo.cc:15:28: warning: 'w2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   p=t[w1];t[w1]=t[w2];t[w2]=p;
                       ~~~~~^~
/in/foo.cc:15:16: warning: 'w1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   p=t[w1];t[w1]=t[w2];t[w2]=p;
           ~~~~~^~~~~~