Steps to reproduce:
1. Create new Unity project using HDRP 3D Template
2. In Project window create Canvas Shader Graph
3. Observe the warning in the Console window

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Actual results: Warning “Output value ‘outMotionVec’ is not complete” is shown after creating Canvas Shader Graph
Expected results: No warnings are shown after creating Canvas Shader Graph

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Reproducible with versions: 6000.0.70f1, 6000.3.10f1, 6000.4.0b11, 6000.5.0a8

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Tested on (OS): macOS Silicon Tahoe 26.3 (M1)

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Warning:
{code:java}
Output value 'outMotionVec' is not completely initialized
Compiling Subshader: 0, Pass: Default, Fragment program with <no keywords>
Platform defines: SHADER_API_DESKTOP UNITY_ENABLE_DETAIL_NORMALMAP UNITY_ENABLE_REFLECTION_BUFFERS UNITY_FRAMEBUFFER_FETCH_AVAILABLE UNITY_LIGHTMAP_FULL_HDR UNITY_LIGHT_PROBE_PROXY_VOLUME UNITY_NEEDS_RENDERPASS_FBFETCH_FALLBACK UNITY_PBS_USE_BRDF1 UNITY_SPECCUBE_BLENDING UNITY_SPECCUBE_BOX_PROJECTION UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS
Disabled keywords: SHADER_API_GLES30 SHADER_API_GLES31 SHADER_API_GLES32 UNITY_ASTC_NORMALMAP_ENCODING UNITY_COLORSPACE_GAMMA UNITY_HARDWARE_TIER1 UNITY_HARDWARE_TIER2 UNITY_HARDWARE_TIER3 UNITY_LIGHTMAP_DLDR_ENCODING UNITY_LIGHTMAP_RGBM_ENCODING UNITY_METAL_SHADOWS_USE_POINT_FILTERING UNITY_NO_DXT5nm UNITY_NO_SCREENSPACE_SHADOWS UNITY_PBS_USE_BRDF2 UNITY_PBS_USE_BRDF3 UNITY_PRETRANSFORM_TO_DISPLAY_ORIENTATION UNITY_UI_ALPHACLIP UNITY_UI_CLIP_RECT UNITY_UNIFIED_SHADER_PRECISION_MODEL UNITY_VIRTUAL_TEXTURING
{code}