What It Means & How to Fix It in UE5

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🧠 Why You’re Seeing This Error

This is a high-level error that means the shader could not be compiled for Shader Model 5 (SM5), which is the default for most modern PC, console, and high-end platforms.

SM5 = Shader Model 5.0 = DirectX 11+, high-end PC rendering tier in UE5

Unreal Engine will throw this error if:

• The shader contains syntax or semantic errors
• You’re using unsupported functions or structures
• Your custom .usf/.ush shader has invalid code or macros
• A material references a function or node that fails to compile in SM5

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💥 Example Error Message

LogShaderCompilers: Error: Shader failed to compile for platform SM5: /MyShaders/MyCustomShader.usf(47,8): error X3000: syntax error: unexpected token

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🛠️ Common Shader Scenarios That Cause This

❌ HLSL Syntax or Typo Error in .usf File

float3 color = float3(1, 0, 1 // ❌ Missing closing parenthesis

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❌ Invalid Intrinsics for SM5

float val = WaveActiveSum(input); // ❌ Requires Shader Model 6

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❌ Incorrect Sampler or Resource Declaration

SamplerState mySampler;
SamplerState mySampler; // ❌ Duplicate declaration

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❌ Material Graph Node That Fails to Compile in SM5

- Custom expressions or logic that only work in mobile/low-end shaders may fail in SM5
- Too many textures, wrong math, or division-by-zero logic

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✅ How to Fix SM5 Shader Compile Failures in UE5 – Step-by-Step

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✔️ 1. Open the Full Output Log or Shader Compiler Log

Go to:

Window → Developer Tools → Output Log

Search for error X or failed to compile for platform SM5. You’ll usually see the exact file, line number, and error reason.

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✔️ 2. Fix the Underlying Shader Error (e.g., X3000, X3004, X4509)

Example fix:

// Error: X3000: unexpected token
float3 color = float3(1, 0, 1); // ✅

Once the root error is resolved, the SM5 compile will succeed.

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✔️ 3. Use #if Blocks to Exclude Unsupported Code

#if PLATFORM_SUPPORTS_SM5
    float result = SomeAdvancedFeature();
#endif

Or:

#if MATERIAL_SHADINGMODEL_SUBSURFACE
    // only include this logic in SM5
#endif

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✔️ 4. Use ShaderCompileWorker to Rebuild and Track Errors

You can rebuild shaders using:

ShaderCompileWorker -clean

Or delete DerivedDataCache/ and restart the engine to force recompilation.

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✅ Summary: How to Fix “Shader Failed to Compile for Platform SM5” in UE5

Cause	Fix
HLSL syntax errors	Check the line number and correct the code
Intrinsics or features not valid in SM5	Use SM5-supported alternatives or wrap in #if blocks
Custom Material/Function bug	Fix material node logic or simplify expressions
Unsupported platform code in shader	Separate logic using conditional compilation macros