This should make our preferred solution to #6538 easier to
implement, avoid a bunch of potential nastiness with excessive
int-vs-double math, and generally make the code there a little less
scary.
"But wait!" you say. "Is it really safe to do this? Won't the
results come out differently?"
Yes, but not much. We now round every weighted bandwidth to the
nearest byte before computing on it. This will make every node that
had a fractional part of its weighted bandwidth before either
slighty more likely or slightly less likely. Further, the rand_bw
value was only ever set with integer precision, so it can't
accurately sample routers with tiny fractional bandwidth values
anyway. Finally, doing repeated double-vs-uint64 comparisons is
just plain sad; it will involve an implicit cast to double, which is
never a fun thing.
This gives us a few benefits:
1) make -j clean all
this will start working, as it should. It currently doesn't.
2) increased parallel build
recursive make will max out at number of files in a directory,
non-recursive make doesn't have such a limitation
3) Removal of duplicate information in make files,
less error prone
I've also slightly updated how we call AM_INIT_AUTOMAKE, as the way
that was used was not only deprecated but will be *removed* in the next
major automake release (1.13).... so probably best that we can continue
to bulid tor without requiring old automake.
(see http://www.gnu.org/software/automake/manual/html_node/Public-Macros.html )
For more reasons why, see resources such as:
http://miller.emu.id.au/pmiller/books/rmch/
I don't personally agree that this is likely to be easy to exploit,
and some initial experimention I've done suggests that cache-miss
times are just plain too fast to get useful info out of when they're
mixed up with the rest of Tor's timing noise. Nevertheless, I'm
leaving Robert's initial changelog entry in the git history so that he
can be the voice of reason if I'm wrong. :)
This makes the V=1 or V=0 automake silent build options display (or hide)
the full command line used.
GEN foo.bar
will be seen rather than the full command.
As with all automake silent rules, "make V=1" will output the full command.
$ make V=1 # will temporarily disable them
otherwise you see:
CC foo.c
rather than the giant long bulid line.
This makes it significantly easier to spot compiler warnings etc.
Additionally, make them conditional, so we won't error on automake <
1.11
(commits squashed by nickm.)
