onnx2c/src/nodes/cast.cc:36: virtual void toC::Cast::resolve(): Assertion `false' failed.

[PasaOpasen]

Tried to compile this model https://dropmefiles.com/MkdyS

with structure

what can be wrong?

[kraiskil]

What is happening here is, as you write in the title of this issue, you are hitting this error.

This is an unimplemented feature in onnx2c.
I don't see the full output of onnx2c, but if the error message linked to above is not printed out, then it is also an error in onnx2c.

The entire concept of a cast operation should be folded into the output of the predecessor node of the cast, as having a separate node just means a redundant copy of data. On the other hand, the C compiler should maybe have such an optimization pass?

[PasaOpasen]

╭─ pasa  ~/Job/__tmp/onnx2c/build  📁 4 🗎 9 🔗 0   master 
╰> $ ./onnx2c ../../craft_fix_input.onnx > model.c
2022-12-29 21-07-35.866 [Fatal] (resolve) Unimplemented casting to requested type
onnx2c: /home/pasa/Job/__tmp/onnx2c/src/nodes/cast.cc:36: virtual void toC::Cast::resolve(): Assertion `false' failed.

its whole stack

[shubham0204]

@kraiskil is there any update to this error?

2024-02-09 09-56-10.197 [Info] (onnx_ir_version) Model has multiple opset versions.
2024-02-09 09-56-10.283 [Info] (resolve) 'Cast' node found.
2024-02-09 09-56-10.284 [Info] (resolve) 'Cast' node found.
2024-02-09 09-56-10.284 [Info] (resolve) 'Cast' node found.
2024-02-09 09-56-10.284 [Info] (resolve) 'Cast' node found.
2024-02-09 09-56-10.284 [Warn] (Elementwise) Round operand implementation is not strictly conformant
2024-02-09 09-56-10.285 [Info] (resolve) 'Cast' node found.
2024-02-09 09-56-10.285 [Fatal] (resolve) Unimplemented casting to requested type
onnx2c: ~/onnx2c/src/nodes/cast.cc:34: virtual void toC::Cast::resolve(): Assertion `false' failed.

[kraiskil]

@shubham0204 sorry, no.
I've been working in the background for the possibility for optimizing input onnx networks (folding Casts away being one of them), so I didn't pay much attention to improving Cast.

Looking at the code at src/nodes/cast.cc:34, it should be fairly straight-forward to extend to support other datatypes. Unfortunately onnx doesn't seem to have any backend test for integer casting, so I am reluctant to add such code "blindly". I guess it could be added even without a unittest as long as someone has tested the patch to be working...

[kraiskil]

Might be fixed now, please re-open new issue, if not.