[Bug fortran/34533] DTIME returns total process time and not since last invocation

[sgk at troutmask dot apl dot washington dot edu]

------- Comment #9 from sgk at troutmask dot apl dot washington dot edu  2007-12-20 22:27 -------
Subject: Re:  DTIME returns total process time and not since last invocation

On Thu, Dec 20, 2007 at 09:39:29PM -0000, dfranke at gcc dot gnu dot org wrote:
> 
> > Daniel, are you working on this PR?
> 
> Sort of. Finished the library part.
> 
> Btw, CPU_TIME has a fallback implementation using times(2). As "times() 
> returns  the  number of clock ticks that have elapsed since an arbitrary
> point in the past", it is IMO unsuitable to be used with CPU_TIME.
> CPU_TIME is supposed to return a "value representing the elapsed CPU
> time in seconds [since start of the program]". Thus, I ditched this
> fallback for the common implementation.
> 

Actually, you don't need to remove the fallback because Niote 13.8
in the F95 standard makes it clear that the initialize time does not
need to be referenced to zero.

>From Note 13.8:

  The start time is left imprecise because the purpose is to time
  sections of code, as in the example.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34533