Re: [Plplot-devel] Problem builiding the Python bindings on Windows using MS VC/C++

[Alan W. I. <ir...@be...>]

On 2013-10-21 22:11+0100 Andrew Ross wrote:

>
> Alan,
>
> [... T]he rounding issues are not an intrinsic 32-bit issue. With a 32-bit
> version of Debian unstable (running under pbuilder) I get completely clean
> results for make test_diff_psc, with the exception of stdout for the python
> example 23. This is with python 2.7.5.

Hi Andrew:

I have just implemented a VALGRIND_ALL_TESTS option (revision 12616).
(For others here, this option is OFF by default and is also OFF if
there is no valgrind installed.  Valgrind is normally not installed on
Windows platforms since valgrind does not work for that case.)

Will you try VALGRIND_ALL_TESTS on your 32-bit system?  (Use the
-DVALGRIND_ALL_TESTS=ON cmake option and run the test_c_psc target as
described in the commit message.)

When I tried that on my 64-bit Linux system I discovered plcolorbar
memory management issues which I am planning to look at this evening.
So with luck I should be able to achieve valgrind perfect results for
all our examples in the 64-bit case.

If tomorrow (Tuesday) your 32-bit system also yields perfect valgrind
results, then that goes a long way toward proving we have good memory
management for our C library and there are no relevant bugs in the
Linux version of gcc for both 32 and 64 bits. Of course, then our
screwed up results _where Python is known to have the same plplot
arguments as in the equivalent C example_ would also imply the
possibility of a bug in the MinGW form of gcc that screws up the
memory management for our core C library. (I have presented that possibility
in general terms without reference to the number of bits since we
don't yet know what might be revealed by a 64-bit test for the MinGW
case.)

Meanwhile, I have yet to see any false positives from gcc-4.7.2 for
-O3 -Wuninitalized.  So I hope you keep plugging away on those
generated by our swig interface (not only for Python, but also for
Java, Lua, and Octave), and I will try to address the rest of the
uninitialized warnings for code in the src directory and also the bad
valgrind results for plcolorbar that I ran into above.  It is a good
goal to clean up all these memory management and uninitialized
variable issues in any case (even if it turns out none of the fixups
have anything to do with the problems encountered when the MinGW
compiler is used).

Alan
__________________________
Alan W. Irwin

Astronomical research affiliation with Department of Physics and Astronomy,
University of Victoria (astrowww.phys.uvic.ca).

Programming affiliations with the FreeEOS equation-of-state
implementation for stellar interiors (freeeos.sf.net); the Time
Ephemerides project (timeephem.sf.net); PLplot scientific plotting
software package (plplot.sf.net); the libLASi project
(unifont.org/lasi); the Loads of Linux Links project (loll.sf.net);
and the Linux Brochure Project (lbproject.sf.net).
__________________________

Linux-powered Science
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