[Pw_forum] a question about fortran

[zyli]

Dear PWSCF users:

   One of my program compiled by ifc output many question
marks '?' for me. I think that it should output star marks
'*' for format problem and nan 'not a number' for mathematic
problem. So what's the meaning of '?'

   I am sorry this question is not really about PWSCF, but I
think somebody in this group may be able to give me an answer 
or some references.

   Thanks.

Sincerely
zyli

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