PGI Fortran Reference manual - The Portland Group

Chapter 6.FORTRAN INTRINSICSAn intrinsic is a function available in a given language whose implementation is handledspecifically by the compiler. Typically, an intrinsic substitutes a sequence of automaticallygeneratedinstructions for the original function call. Since the compiler has an intimate knowledgeof the intrinsic function, it can better integrate it and optimize it for the situation.This section lists the FORTRAN 77 and Fortran 90/95 intrinsics and subroutines and Fortran2003 intrinsic modules. The Fortran processor, rather than the user or a third party, provides theintrinsic functions and intrinsic modules.For details on the standard intrinsics, refer to the Fortran language specifications readily availableon the internet. The Origin column in the tables in this section provides the Fortran languageorigin of the statement; for example, F95 indicates the statement is from Fortran 95.6.1. Intrinsics SupportThe tables in this section contain the FORTRAN 77, Fortran 90/95 and Fortran 2003 intrinsicsthat are supported. At the top of each reference page is a brief description of the statementfollowed by a header that indicates the origin of the statement. The following list describes themeaning of the origin abbreviations.F77FORTRAN 77 intrinsics that are essentially unchanged from the original FORTRAN 77standard and are supported by the PGF77 compiler.F77 extensionThe statement is an extension to the Fortran language.F90/F95The statement is either new for Fortran 90/95 or significantly changed in Fortran 95 fromits original FORTRAN 77 definition and is supported by the PGF95 and PGFORTRANcompilers.F2003The statement is new for Fortran 2003.The functions in the following table are specific to Fortran 90/95 unless otherwise specified.PGI Fortran Reference Guide 89