[gdal-dev] Issue with gdalchksum on Fedora 21 ppc64le?

[Even Rouault]

Le mardi 25 août 2015 07:28:46, Gawade P a écrit :
> Hi Even,
> It looks like I am running into another checksum issue on ppc64le.
> 
> Output on ppc64le:
> gdalchksum.py ../autotest/gdrivers/data/nwt_grd.grd
> 28093
> 32304
> 19624
> 25856
> 
> Output on x86:
> gdalchksum.py ../autotest/gdrivers/data/nwt_grd.grd
> 28093
> 33626
> 20260
> 25856
> 
> There is a mismatch for bands 2 and 3. I am looking at the code in
> frmts/northwood/grddataset.cpp. Would this be the right place?

Yes.

From a quick look it doesn't appear to be the same issue as for HF2. And I've 
actually recompiled GDAL with -fsigned-char on x86_64 to simulate ppc64le 
behaviour regarding char, and the good news is that the autotest suite pass 
fine, so it seems this class of problem isn't widespread in the code base.

Perhaps slighlty different floating-point rounding in the way the colormap is 
computed by nwt_LoadColors() ? Hard to tell.

> Would you recommend raising an issue for this one as well? Please suggest.

You can always open a ticket, at least to keep track of the issue, but that 
doesn't mean it will be automagically adressed. Especially since PPC64LE isn't 
a commonly used platform I guess.

Even

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