More about gfortran & comparison with g77

[Bud Davis]

On Mon, 2005-02-07 at 08:39, Philippe Depondt wrote:
  
> 
> To summarize, gfortran takes twice as much time as g77 writing stuff to 
> a file (two first examples).
 no clue on this...


> But, on top of that, it is 10 times slower when the result file already 
> exists (taking in account user time only, but sys time also shows large
> differences), whereas g77 is insensitive to the existence of an old
> result file...
the difference is the mmap abstraction used in unix.c. when the file
is first created, mmap is not used.  when the files exists, it is used.

 
> I have also noticed that a program compiled with g77 will not only
> overwrite an existing file but erase all previous data (even if the new
> file is shorter that the old one), whereas a gfortran compiled program
> will only overwrite and, when the new file is shorter leave previous
> results. I don't know whether that is relevant.
this is a bug. please make a small example and file a bug report.
 

--bud