Re: DAVEM TPF Grant#2 June 2017 report

+1!

Thanks, Dave. :)

On 08/07/2017 12:19 PM, Dave Mitchell wrote:
> This report covers June up to the 19th, at which point my grant ran out.
> (I'm currently waiting on extension approval, but am doing work funded by
> Booking.com the meantime).
>
> I spent June mainly:
>
> * finishing off the heavy reworking of perl's internal sprintf implementation.
>   This has now been merged into blead. It  contains about 100 commits which
>   fixes bugs, audits the code for possible integer overflows, makes the
>   code simpler - and simpler to understand - and improves performance by
>   around 15%.
>
> * adding a proper test suite for Porting/bench.pl, and fixing the utility
>   up based on the test results. For example at some point the
>   --bisect option broke, but this was never noticed due to no testing.
>  
> * adding a DEBUGGING-build mechanism to detect some classes of
>   bug where pp functions fail to extend the stack before pushing return
>   values. Basically the runops loop sets a high water mark variable before
>   calling the pp function; EXTEND() and similar update that mark, and on
>   return from the pp function, we check whether PL_stack_sp is > the mark
>   and panic if so. This has allowed me to detect and fix several such bugs
>   in core.
>
> Other than that I worked on a few miscellaneous RT tickets.
>
> SUMMARY:
>      15:41 RT #131260 sprintf implementation
>       0:37 RT #131555 heap-buffer-overflow
>       1:57 RT #131575 s// on utf8 string occasionally crashes
>       0:51 RT #131577 heap-use-after-free (READ of size 1) in S_reghop4()
>      21:25 add better tests for Porting/bench.pl
>       4:21 apply accumulated post-5.26 fixes
>       4:29 fix 32-bit builds
>      14:17 fix stack extend overruns
>       4:23 process p5p mailbox
>       2:00 sort out 5.27.1 version numbers
>       1:04 update perldelta
>     ------
>      71:05 TOTAL (HH::MM)
>
>  199.1 weeks
> 2800.0 total hours
>   14.1 average hours per week
>
>

• DAVEM TPF Grant#2 June 2017 report by Dave Mitchell
• Re: DAVEM TPF Grant#2 June 2017 report by Sawyer X