

volatile                    C Keyword                    volatile




Qualify an identifier as frequently changing


The  type qualifier  volatile marks an  identifier as  being fre-
quently changed, either by  other portions of the program, by the
hardware, by  other programs in the  execution environment, or by
any combination of these.  This alerts the translator to re-fetch
the given  identifier whenever  it encounters an  expression that
includes  the  identifier.   In  addition,  an object  marked  as
volatile must be stored at  the point where an assignment to this
object takes place.

***** See Also *****

C keyword, const

***** Notes *****

Although COHERENT recognizes  this keyword, the semantics are not
implemented  in  this  release.   Thus,  storage declared  to  be
volatile might have  references removed by optimizations that the
compiler performs.   The compiler will generate  a warning if the
peephole  optimizer  is  enabled  and  the  keyword  volatile  is
detected.
































COHERENT Lexicon                                           Page 1


