UPSTREAM PR #17749: fix: convert_hf_to_gguf - use existing local chat_template if mistral-format model has one.

[loci-dev]

Mirrored from ggml-org/llama.cpp#17749

Cont. ggml-org/llama.cpp#17712

Some of the new Ministral-3 Instruct variants have local chat templates, unlike previous Mistral models which required community intervention.

Beforehand, Ministral-3 models were converted and given an Unsloth Devstral chat template. This PR ensures Ministral-3 models converted with --mistral-format use their own provided chat templates instead.

It should also affect Mistral-Large-3 as it has its own chat template too - I don't have the resources to test converting it.

[loci-agentic-ai]

Explore the complete analysis inside the Version Insights

Performance Analysis Summary - PR #424

Overview

PR #424 modifies the Python conversion script convert_hf_to_gguf.py to prioritize local chat_template.jinja files for Mistral-format models. This is a metadata-only change affecting model conversion workflow, not runtime inference code.

Performance Impact

Binary Analysis:
All 16 binaries show zero performance change:

• libllama.so, libggml-cpu.so, libggml-base.so, libggml.so, libmtmd.so
• llama-run, llama-cvector-generator, llama-bench, llama-quantize, llama-tts
• llama-gguf-split, llama-tokenize, llama-gemma3-cli, llama-llava-cli, llama-minicpmv-cli, llama-qwen2vl-cli

Power consumption changes: 0.0% across all binaries (variations < 1 nJ, within measurement noise).

Function-Level Analysis:
No functions show response time or throughput changes. Core inference functions remain unaffected:

• llama_decode: No change
• llama_encode: No change
• llama_tokenize: No change
• ggml_backend_graph_compute: No change

Tokens Per Second Impact:
Zero impact on inference throughput. The changes modify conversion-time template selection logic only. Chat templates are embedded as metadata in GGUF files and do not affect token processing during inference.

Code Changes:

• Added local template file existence check (chat_template.jinja)
• Refactored get_community_chat_template() to return path instead of contents
• Unified file reading logic for both local and community templates
• Updated conditional logic to prioritize local templates for Mistral-format models

This PR enables Ministral-3 and Mistral-Large-3 models to use their official templates while maintaining full backward compatibility with existing conversion workflows.