On 3/26/19 8:10 AM, clipka wrote:
> Am 26.03.2019 um 11:46 schrieb William F Pokorny:
>> Quick additional question. Is it the --enable-debug configure flag
>> that - normally - turns on the pov asserts? I've never verified this
>> assumption of mine by creating a pov assert in the code I know should
> To be honest, I haven't a clue. I'm not sure what the `--enable-debug`
> flag does exactly (it's some standard mechanism in the Automake tools),
> nor whether and how assertions are enabled or disabled in Unix builds.
> I'm pretty sure that `--enable-debug` does enable the creation of debug
> information in the binaries, so that a debugging tool can correlate
> binary code addresses with original source code lines, so that you can
> e.g. set breakpoints and step through the code line by line with a
> debugger. I also wouldn't be surprised if it turns off optimizations by
> default, because those tend to re-order instructions and make a
> line-by-line correlation impossible. Whether it does anything beyond
> that I do not know. It might dictate whether `NDEBUG` is defined or not,
> which would conceivably disable/enable assertions.
Back at it this morning.
First, flipping the file name compare so it's ahead of the file position
compare (and assert) works fine too with all the test cases I have that
Second, on enabling the POV_ASSERT source code mechanism, took the time
to do some full compiles with a known fail assert of 1 == 0 and the
short of it for *nix is doing something like:
./configure COMPILED_BY="wfp__POV_DEBUG" CXXFLAGS="-DPOV_DEBUG"
works. The -D<var> form on the define is added as a compiler flag to do
the POV_DEBUG define, which, turns on the POV asserts that exist in the
code (except I guess where not otherwise controlled or hard-set).
Lastly, on the --enable-debug flag, it is not today defining POV_DEBUG
which is what turns on the POV_ASSERTs. Most of my actual debug compiles
use a configure command like:
./configure COMPILED_BY="wfp" --disable-optimiz --disable-strip \
CXXFLAGS="-Og -ggdb fverbose-asm"
so --enable-debug isn't strictly needed for debugging though on line
documentation I read just now indicates - by default anyway - it does
something equivalent given certain arguments. Looks like you can select
what sort of debugging gets turned on - and you can provide a second
argument defining variables explicitly (ie POV_DEBUG) and there is the
NDEBUG you mentioned (boost seems to use this some) getting set by
default if the flag's argument turns debugging off (or the flag's not
used but enabled?). What some documentation says only; Not sure what
works or not for --enable-debug with our current set up without doing a
bunch of compiles and tests. An investigation for another time. The flag
doesn't control the POV_ASSERTs today via NDEBUG in any case - so at
best it might provide another way to define POV_DEBUG using that second
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