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I was a bit rash in assigning this bug to myself - my version of qgis running on Linux loads and displays the shp file fine, making it a bit hard to fix the problem. ogrinfo also gives sensible results.

I tested on linux and the file loads fine for me too - I will test on mac and see if I can reproduce the issue.

I had a more detailed look at this.

0   <<00000000>>     0xffff0691 +bzero + 145 (cpu_capabilities.h:187)
1   libSystem.B.dylib       0x9000adb8 strncpy + 216
2   libgdal.1.dylib         0x01ba934c DBFIsAttributeNULL + 39
3   libgdal.1.dylib         0x01c4ca86 SHPReadOGRFeature(SHPInfo*, DBFInfo*, OGRFeatureDefn*, int) + 274
4   libgdal.1.dylib         0x01c2f1cf OGRShapeLayer::GetNextFeature() + 239
5   ogrprovider.so          0x175a1fff [[QgsOgrProvider]]::getNextFeature(std::list<int, std::allocator<int> > const&, int) + 161

So the crash is occurring withing gdal itself. There doesnt seem to be any way to manage a bad read in src/providers/ogr/qgsogrprovider.cpp:

    330     OGRFeature *fet;
    331     while ((fet = ogrLayer->GetNextFeature()) != NULL) {
    332       if (fet->GetGeometryRef())
    333         break;
    334     }

If the ogr call GetNextFeature fails there is no error that is returned and no decent way that I can see to smoothly handle the problem. I will need to write to the gdal list and see if there is any option for a fix but it doesnt look promising at this point....

As we talked with Tim and Frank on the #gdal, the problem is that attached jrline.shp file includes truncated features with id 62 and it seems invalid shapefile. I'm eager to learn what's wrong with this file. What's certain thing, is that fseek and fread fail on this shapefile (lines 1451-1452 in the shpopen.c file).

I fixed it in OGR and its Shape driver adding stronger tests to results of Shapefile operations.
The main changes have been applied to SHPReadOGRFeature() function.
So, now GetFeature() and GetNextFeature() will return NULL if Shapelib (fseek/fread, see above) fail to read shape object from layer.

Here is sample test trying to read feature 62 from jrline.shp.

mloskot:~/dev/gdal/bugs/qgis_200$ ~/dev/gdal/_cvs/gdal/ogr/ogrinfo -fid 62 jrline.shp jrline
INFO: Open of @jrline.shp'
      using driver @ESRI Shapefile' successful.

Layer name: jrline
Geometry: Line String
Feature Count: 63
Extent: (135.613700, 34.820579) - (135.890390, 35.085503)
Layer SRS WKT:
PROJCS["JGD2000_Japan_Zone_6",
    GEOGCS["GCS_JGD_2000",
        DATUM["JGD_2000",
            SPHEROID[[GRS_1980]],
        PRIMEM[[Greenwich]],
        UNIT[[Degree]],
    PROJECTION[[Transverse_Mercator]],
    PARAMETER[[False_Easting]],
    PARAMETER[[False_Northing]],
    PARAMETER[[Central_Meridian]],
    PARAMETER[[Scale_Factor]],
    PARAMETER[[Latitude_Of_Origin]],
    UNIT[[Meter]]
[[ArcID]]: Real (16.6)
[[ArcType]]: String (20.0)
[[FromNode]]: Real (16.6)
[[ToNode]]: Real (16.6)
[[LeftPoly]]: Real (16.6)
[[RightPoly]]: Real (16.6)
Length: Real (16.6)
[[NumericUse]]: Real (16.6)
[[TextUserId]]: String (50.0)
SEQUENTIAL: Real (16.6)
ENTITY: Real (16.6)
ARCNUM: Real (16.6)
CLASS: Real (16.6)
ERROR 3: Error in fseek() or fread() reading object from .shp file.
ERROR 1: Couldn't read geometry from shape with feature id (62), likely data is corrupted.
Unable to locate feature id 62 on this layer

As you can see, there are 3 error messages at the end of the output:
ERROR 3 - comes from shpopen.c
ERROR 1 - comes from SHPReadOGRFeature() function and indicates that Shapelib's SHPReadObject() failed (what ERROR 3 confirms).
Unable to locate feature id 62 on this layer - comes from ogrinfo utility.

So, obviously, in case of similar problems in QGIS, you should see first two messages in the console.

In case of GDAL/OGR problems, don't hesitate to give me a note.