Question

I declare my struct in a header file like so:

typedef struct MyStruct{
    int test;
} MyStruct;

@interface StructTestingFile
MyStruct *originalStruct;
@end

Then from the .mm file, I call

originalStruct = loadTestInt();

In the C file, here is what I’m doing:

extern "C" MyStruct* loadTestInt()
{
    MyStruct *aStruct;

    aStruct->test = 1;

    return aStruct;
}

Every time it crashes on assigning aStruct->test = 1. What am I doing incorrectly?

Answer 1

You’re creating a pointer but not allocating memory for the struct itself;

MyStruct *aStruct;

aStruct = (MyStruct*)malloc(sizeof(MyStruct));

aStruct->test = 1;