[BUG] The pass "eliminate_shape_op" causes output mismatch

The pass "eliminate_shape_op" causes output mismatch

Issue
eliminate_shape_op (onnxoptimizer 0.4.2) causes output drift in a subset of filtered non-ok cases even when ORT graph optimizations are disabled. case_03181_seed45441358 shows mismatches (v4_0, v25_0), and case_05898_seed66957281 shows NaN mismatches (v14_0).

Environment

• Ubuntu 20.04
• Python 3.10
• onnx==1.19.0
• onnxruntime==1.19.2
• onnxoptimizer==0.4.2 (latest)

Repro steps (run from this folder)

1. Download and unzip the attached archive below, then cd into the extracted directory

eliminate_shape_op_repro.tar.gz

tar -xzvf eliminate_shape_op_repro.tar.gz
cd eliminate_shape_op_repro

2. Create a Python 3.10 virtual environment and install dependencies:

python -m venv .venv
source .venv/bin/activate
pip install --upgrade pip
pip install -r requirements.txt

3. Optimize each case with only eliminate_shape_op:

python optimize_model.py --case case_03181_seed45441358

4. Run the differential test (ORT optimizations disabled) to compare optimized vs reference:

python diff_test.py --case case_03181_seed45441358

Expected
eliminate_shape_op should be semantics-preserving; applying the pass alone should not change any output values.

Differential Test Output Details

1. case_03181_seed45441358

Case: case_03181_seed45441358
Mismatched outputs (optimized vs reference):
	v4_0 (output[11]): max_abs=3.352e+00, max_rel=6.005e-01, shape=(1, 135, 17)
	v25_0 (output[12]): max_abs=5.664e+00, max_rel=4.489e+00, shape=(57, 45, 17)
Overall: max_abs=5.664e+00, max_rel=4.489e+00

Attachments

• README.md (this document)
• requirements.txt (dependency versions)
• optimize_model.py (runs only fuse_consecutive_squeezes and saves model.opt.onnx)
• diff_test.py (runs original vs optimized with oracle inputs and reports max_abs/max_rel)
• case_03181_seed45441358/ (contains model.onnx original model, oracle.pkl input data for both original and optimized models)

Start by running optimize_model.py for case_03181_seed45441358, then use diff_test.py with ORT graph optimizations disabled to reproduce the mismatch. Read the pass-related behavior described in the repro and compare the optimized model with model.onnx using oracle.pkl. Done means applying eliminate_shape_op alone preserves all output values, including the reported cases.