Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
651 views
in Technique[技术] by (71.8m points)

c++ - 0xC0000005: Access violation reading location 0x00000000

I'm having a very strange issue with a space invaders game I'm working on. Basically I get an access violation error:

Unhandled exception at 0x5edad442 (msvcr100d.dll) in SpaceInvaders.exe: 0xC0000005: Access violation reading location 0x00000000.

when I include the piece of code below. visual studio takes me to "strcmp.asm" when debugging. Note that Im not using strcmp() in any of my code. Is there anything wrong with the code, or is this a problem beyond the scope of what I've included? Thanks for any help

const char* invarray[] = {"invader0.png", "invader1.png", "invader2.png", "invader3.png", "invader4.png"}; 
int i=0;
//Creates 55 invaders
for (int y=0; y<250; y+=50){
    for (int x=0; x<550;x+=50){
        Invader inv(invarray[y/50], x+50, y+550, 15, 15, 1, false, 250);
        invaders[i] = inv;
    }
}

Invader constructor:

Invader::Invader(const char *pic, int x, int y, int w, int h, bool dir, bool des, int point) : MovingObject(pic, x, y, w, h) , direction(dir), destroyed(des), b(0), points(point){};

MovingObject Constructor

MovingObject::MovingObject(const char *pic, int x, int y, int w, int h):picture(pic), positionX(x), positionY(y), width(w), height(h) {};
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

"Access violation reading location 0x00000000" means that you're derefrencing a pointer that hasn't been initialized and therefore has garbage values. Those garbage values could be anything, but usually it happens to be 0 and so you try to read from the memory address 0x0, which the operating system detects and prevents you from doing.

Check and make sure that the array invaders[] is what you think it should be.

Also, you don't seem to be updating i ever - meaning that you keep placing the same Invader object into location 0 of invaders[] at every loop iteration.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...