On Sat, Jun 16, 2018 at 06:56:49PM +0100, graham stott wrote: > if i read this correctly it appears that IMPURE/PURE are not the normal > pure attribute used by gcc but some entirely diff attribute specific to > FORTAN so people are taking about different things >
PURE and IMPURE are prefix-spec in Fortran. A Subprogram that is marked as PURE must meet additional requirements. Those requirements essentially eliminate the possibility of a function having side effects. A subprogram marked as IMPURE can also meet those additional requirements. BTW, the name of the language is Fortran (not FORTRAN). It's been Fortran for more than 27 years. -- Steve
