Having space in Custom Attribute name breaks compilation

How to reproduce:

1. Import the attached VFX
2. Drag it to the scene view
3. Observe errors in the console and that effect is not rendered

 

Shader error in 'Hidden/VFX/Custom attributes/System/Output Particle Quad': syntax error: unexpected token 'B_a' at line 118 (on metal)

Compiling Subshader: 0, Pass: <Unnamed Pass 2>, Fragment program with INSTANCING_ON
Platform defines: SHADER_API_DESKTOP UNITY_ENABLE_DETAIL_NORMALMAP 

OutputUpdate': syntax error: unexpected token 'B_a' at kernel CSMain at attributes.vfx(51) (on metal)

 

[Custom attributes] [System] OutputUpdate.compute: Kernel at index (0) is invalid
UnityEditor.PreviewRenderUtility:Render (bool,bool)
VisualEffectAssetEditor:OnInteractivePreviewGUI (UnityEngine.Rect,UnityEngine.GUIStyle) (at /Users/vita.skruibyte/Documents/unity/packages/com.unity.visualeffectgraph/Editor/Inspector/VFXAssetEditor.cs:467)
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)