RuntimeError explanation
2025-10-222 turns2,604 charsgpt-5-mini📷 multimodal
Summary
User is seeking an explanation for a Python RuntimeError error message.
Messages
what is this error:
From the screenshot you shared, the main error is here:
```
RuntimeError:
...
raise RuntimeError(
"Unsloath: No working quantizer found in {llama_cpp_folder}\n"
```
This happens at the step where `unsloth` is trying to convert your model to GGUF format:
```python
model.save_pretrained_gguf(MERGED_DIR, quantization_method="q4_k_m")
```
The error occurs because the `llama.cpp` folder does not contain a working quantizer. Essentially:
1. `unsloth` is attempting to use `llama.cpp` tools to convert the model to GGUF format.
2. It checks your system for `llama.cpp` binaries using `check_llama_cpp()`.
3. It either doesn't find the binaries or they are incomplete, so it raises a `RuntimeError`.
Additional context from the log:
- The message: `Unsloath: llama.cpp folder exists but binaries not found – will rebuild` shows it tried to rebuild `llama.cpp`.
- Then it fails at the quantizer step because the rebuild didn't produce a working binary.
---
**Why this happens:**
- `unsloth` requires `llama.cpp` to be compiled with a working `quantize` tool.
- Either compilation failed, or your environment (Python 3.13, Linux) caused a binary incompatibility.
- Sometimes `llama.cpp` install via `unsloth` is skipped if certain dependencies are missing.
---
**How to fix:**
1. Make sure your system has `cmake` and a C++ compiler installed (`g++`, `clang`).
```bash
sudo apt update
sudo apt install cmake build-essential
```
2. Delete the existing `llama.cpp` folder under `unsloth` so it forces a rebuild:
```bash
rm -rf ~/ai/renovai/unsloth/lib/python3.13/site-packages/unsloth_zo/llama_cpp
```
3. Re-run your Python code to let `unsloth` rebuild `llama.cpp` binaries.
4. If it still fails, you can manually build `llama.cpp`:
```bash
git clone https://github.com/ggerganov/llama.cpp
cd llama.cpp
make
```
5. After building, point `unsloth` to your manually built `llama.cpp` folder when calling `save_pretrained_gguf`.
---
The **secondary warning**:
```
UserWarning: Model is not a PeftModel (no Lora adapters detected). Skipping Merge.
```
- This is not fatal. It just says there’s no LoRA adapter in your model, so `save_pretrained_merged` will essentially save the original weights.
---
✅ **TL;DR**: Your error is because `unsloth` cannot find a working quantizer in `llama.cpp`. You need to make sure `llama.cpp` is properly built with `cmake` and a C++ compiler.
I can give you the exact shell commands to rebuild it for your Python 3.13 environment so `save_pretrained_gguf` works. Do you want me to do that?
gpt-5-mini