c++ - OGRFeature setting multiple fields -

hi start off with:

using gdal compiled xerces

coding in c++ qt creator version 5.4.1

so problem im trying use gdal create own esri shapefile, strange runtime error when trying add multiple fields

example:

    // create ogr feeature     ogrfeature* ogr_feature;     // set bunch of fields     ogr_feature->setfield("blah","blah");     ogr_feature->setfield("foo","foo");     ogr_feature->setfield("bar","bar");     ogr_feature->setfield("test","test"); 

when run program once hits part gives out error message:

error :1 invalid index -1

i'm not sure what's causing this. i've tried taking out 1 , thats fine doesnt give me errors. more 1 throws error.

anyone know how fix this/ why doing it?