Segfault when attempting to free a slice inside a struct

[open tinsel]

I have the following struct:

pub const MyStruct = struct {
    allocator: Allocator,
    count: u16,
    code: []u8,
};

This is the function I use to create it:

pub fn initMyStruct(allocator: Allocator) !*MyStruct{
    const code = try allocator.alloc(u8, 8);
    var result = MyStruct{
        .allocator = allocator,
        .count = 0,
        .code = code,
    };

    return &result;
}

Here's how I'm trying to destroy it (doesn't work):

pub fn freeMyStruct(my_struct: *MyStruct) void {
    var allocator = my_struct.allocator;
    freeArray(MyStruct, allocator, chunk.code);
}

pub fn freeArray(comptime T: type, allocator: Allocator, pointer: []T) void {
    allocator.free(pointer);
}

I get a segfault when trying to free the slice. What am I doing wrong?

[sage owl]

you're returning a pointer to memory that doesn't exist

not the stuff you're allocating, but when you return &result

because you make result on the stack, it doesn't necessarily exist outside of that initMyStruct function

you probably want to return a MyStruct value rather than a pointer to MyStruct

also i'm not sure where the chunk.code bit is coming from, i'm assuming that's some global thing?

the typical zig way to do this would be to have everything in a single struct, looking something like this:

pub const MyStruct = struct{
  allocator: Allocator, 
  count: u16,
  code: []u8,

  pub fn init(allocator: Allocator)!MyStruct{
    return MyStruct{
      .allocator = allocator, 
      .count = 0,
      .code = try allocator.alloc(u8, 8),
    };
  }

  pub fn deinit(self: MyStruct){
    self.allocator.free(code);
  }
};

[open tinsel]

Thank you very much!