From cb637db5d619bfdb9be592220ebf206e96be7402 Mon Sep 17 00:00:00 2001
From: Robert Konrad <git2016@robdangero.us>
Date: Fri, 24 Mar 2017 15:58:54 +0100
Subject: [PATCH] Handle GL_ARB_derivative_control

---
 spirv_glsl.cpp | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/spirv_glsl.cpp b/spirv_glsl.cpp
index 78e9f65c..86e63bf3 100644
--- a/spirv_glsl.cpp
+++ b/spirv_glsl.cpp
@@ -5041,18 +5041,42 @@ void CompilerGLSL::emit_instruction(const Instruction &instruction)
 
 	case OpDPdxFine:
 		UFOP(dFdxFine);
+		if (options.es)
+		{
+			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
+		}
+		if (options.version < 450)
+			require_extension("GL_ARB_derivative_control");
 		break;
 
 	case OpDPdyFine:
 		UFOP(dFdyFine);
+		if (options.es)
+		{
+			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
+		}
+		if (options.version < 450)
+			require_extension("GL_ARB_derivative_control");
 		break;
 
 	case OpDPdxCoarse:
+		if (options.es)
+		{
+			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
+		}
 		UFOP(dFdxCoarse);
+		if (options.version < 450)
+			require_extension("GL_ARB_derivative_control");
 		break;
 
 	case OpDPdyCoarse:
 		UFOP(dFdyCoarse);
+		if (options.es)
+		{
+			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
+		}
+		if (options.version < 450)
+			require_extension("GL_ARB_derivative_control");
 		break;
 
 	case OpFwidth: