How to reproduce:
1. Open the attached "IN-137903_Shader Warning Bug Report.zip" project
2. In the Project tab, find the "ProceduralBlurredImage.shader" file and select it
3. In the Inspector, observe the "(...) Errors and (...) Warnings:" field
Actual result: A warning is present in the field saying "use of potentially uninitialized variable (sdfQuadrilateral)"
Expected result: No warning is present
Reproducible with: 6000.0.0b11, 6000.0.73f1, 6000.3.13f1, 6000.4.3f1, 6000.5.0b4, 6000.6.0a3
Could not test with: 2023.1.0a1, 2023.3.0a2 (FlexibleImage plugin throws errors in console, different warning in shader)
Reproducible on: Windows 11
Not reproducible on: No other environments tested