c++ - Getting a segfault from a file read to an array of object pointers? -


so i've declared array of pointers like

items* _items[arrsize];

basically goal of using them array of objects (one meat, 1 produce) dynamically decided on run time. i'm calling following function in constructor , i've identified reason keep segfaulting before main function.

void inventory::loadrecs(){     datafile.open(_filename);     int = 0;      char c;     //create fileif doesnt exist     if(datafile.fail()){         datafile.clear();         datafile.close();         datafile.open(_filename, ios::out);         datafile.close();     }     else{        //read file        while(!datafile.eof()){            if(_items[i] != nullptr){                delete _items[i];            }            c = datafile.get();            if(c == 'p'){                _items[i] = new produce;            }            if (c == 'm'){                _items[i] = new meat;            }            datafile.ignore();            _items[i]->load(datafile);             i++;            datafile.ignore(); //ignore endl        }        _noofitems = i;        datafile.close();    } }

the text file i'm reading straight forward reading like

p,123,carrots,0.66,[newline] first character identifies kind of product (meat or produce) , rest of line read in load function.

my inventory class looks this:

 class inventory{     char _filename[256];     item* _items[5];     std::fstream datafile;     int _noofitems; }

and constructor initializes , calls loadsrecs (which segfault from)

i'm willing bet aren't initializing array of pointers , check against nullptr failing, , calling delete on garbage pointer resulting in undefined behavior.

unless have constructor omitted code, pointers default initialized resulting in indeterminate values.

since in code have shown, using new produce; , new meat;, i'll assume have written new inventory; or inventory i;. if instead, included parenthesis (or braces in c++11) new produce(); or inventory i{};, value initialization zero initialization of pointers. result in behavior seemingly expect.


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