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Technically they are equivalent, but in practice different. What's happening is that the compiler will hoist the declaration of these arrays outside of the loops. This is standard practice for the compiler and happens before the OpenACC directives are applied. What should happen is that then these arrays are implicitly privatized within the scoping unit they are declared. However the compiler doesn't currently track this so the arrays are implicitly copied into the compute region as shared arrays. If you add the flag "-Minfo=accel", you'll see the compiler feedback messages indicating the implicit copies.

I have an open issue report requesting this support, TPR #31360, however it's been a challenge to implement so not in a released compiler as of yet. Hence until/if we can fix the behavior, you'll need to manually hoist the declaration of these arrays and then add them to a "private" clause.