Is there a way to build this struct on the heap or any alternative to this `large_stack_frames` issue?

(1) Main logic to solve the issue:

You need to break up your large struct into smaller structs (eg: as smaller/categorized groupings).
You can have an array of structs, where the total length of values in each struct would add up to the required total of your current "too large" struct.

This way the compiler is only dealing with one thing at a time. Such as "one (master) array of 10 structs" or "one struct with 100 values" where some struct values (in themselves) can be arrays of further multiple data.

• Try breaking up your strut into smaller parts (categories)
• Try using Tuples to hold mixed data, on the heap.

use multiple structs or tuples if data is said to be too large for one variable.

(2) Possible inspiration from other file formats:

You could try the logic of file formats that have to store multiple data, eg: multimedia files.
One example is Apple's MOV file type. MOV has to store audio, video, image, text and numbers in one unit.

Having such a code part allows you to store large data on the heap in an array. It will be like a "virtual" data file but holding only those values that are needed to be fed as input for the in-app struct variables.

The values themselves, to put into the array, could come from a loaded binary file or some user input via checkboxes, or updated as the result of some function like "updategamestats( mystructsarray );".

Secondly. On the heap create an array that holds some loaded/user input data (for feeding onto structs)

Each entry could be in this example format:

[SIZE =2 bytes] , [TYPE =1 byte] , [DATALEN = 2 bytes] , [DATA = bytes length by DATALEN]

You can use Tuples to send data to a function that returns an Array. The output array ca be concated to the main array on the heap.

Tuples can hold mixed data.

let mytuple = ("struct03" , "Option" , "createdat", 17.35 , "pm" );
println!("{} {} {} {} {}", mytuple.0, mytuple.1, mytuple.2 , mytuple.3 , mytuple.4 );

In the above example tuple, the format is:
[ whichstructtoupdate , thevaluetype , keyactual , valueactual , miscextra_value ]

The writing function will put these values (can be text or numerical) into the Array as byte values. I can help you with this part if you are interested in writing such a bytes Array on the heap.