Godot 4.4dev3: shader compilation error when "Disable Receive Shadows" is Enabled

[Lod6]

Tested versions

• Reproducible in 4.4 dev3

System information

Windows 11 - (rendering method: Mobile)

Issue description

When I check "Disable Receive Shadows" in the material settings, the following error occurs during shader compilation:

` servers/rendering/renderer_rd/forward_mobile/scene_shader_forward_mobile.cpp:193 - Condition "!shader_singleton->shader.version_is_valid(version)" is true.
servers/rendering/renderer_rd/shader_rd.cpp:300 - Error compiling Fragment shader, variant #0 ().
servers/rendering/renderer_rd/shader_rd.cpp:301 - Failed parse:
WARNING: 0:79: '' : all default precisions are highp; use precision statements to quiet warning, e.g.:
"precision mediump int; precision highp float;"
ERROR: 0:2519: 'i' : undeclared identifier
ERROR: 0:2519: '' : missing #endif
ERROR: 0:2519: '' : compilation terminated
ERROR: 3 compilation errors. No code generated.

`

Steps to reproduce

1. Create a new StandardMaterial3D resource
2. Check "Disable Receive Shadows" in Shadows tab

Minimal reproduction project (MRP)

receiveshadowsbug.zip

[tetrapod00]

Confirmed on 4.4.dev3. Can't reproduce on 4.4.dev2.

[matheusmdx]

Bisecting points to #83360 as the culprit, @ywmaa

[ywmaa]

Does this issue happen with Vulkan mobile only ?

[matheusmdx]

Does this issue happen with Vulkan mobile only ?

Tested rn and seems to affect only vulkan mobile.