Firstprivate and Lastprivate (2)

• Parallelizing a loop and not knowing whether there are side effects?

subroutine foo(n)

common /foobar/a(1000),b(1000),x

c$omp parallel do shared(a,b,n) lastprivate(x)

do 10 i=1,n

x=a(i)**2 + b(i)**2

10 b(i)= sqrt(x)

end

Use lastprivate because don’t

know where or if x in common

/foobar/ will be used again

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