foo.cc: In function 'void quickSort(int*, int, int)':
foo.cc:90:14: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   90 |   pos=segment(a,start,pos-1);
      |       ~~~~~~~^~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:90:14: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   90 |   pos=segment(a,start,pos-1);
      |       ~~~~~~~^~~~~~~~~~~~~~~
foo.cc:87:6: note: 'pos' was declared here
   87 |  int pos;
      |      ^~~

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