foo.cc: In function 'int main()':
foo.cc:9:5: warning: 'a' is used uninitialized in this function [-Wuninitialized]
    9 |  z=a*0.1+b*0.2+c*0.2+d*0.5;
      |    ~^~~~
foo.cc:9:11: warning: 'b' is used uninitialized in this function [-Wuninitialized]
    9 |  z=a*0.1+b*0.2+c*0.2+d*0.5;
      |          ~^~~~
foo.cc:9:17: warning: 'c' is used uninitialized in this function [-Wuninitialized]
    9 |  z=a*0.1+b*0.2+c*0.2+d*0.5;
      |                ~^~~~
foo.cc:9:23: warning: 'd' is used uninitialized in this function [-Wuninitialized]
    9 |  z=a*0.1+b*0.2+c*0.2+d*0.5;
      |                      ~^~~~

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