diff --git a/examples/15-shadowmaps-simple/shadowmaps_simple.cpp b/examples/15-shadowmaps-simple/shadowmaps_simple.cpp
index 13d86afb..513a37f2 100644
--- a/examples/15-shadowmaps-simple/shadowmaps_simple.cpp
+++ b/examples/15-shadowmaps-simple/shadowmaps_simple.cpp
@@ -311,7 +311,6 @@ int _main_(int /*_argc*/, char** /*_argv*/)
 
 		// Floor.
 		bx::mtxMul(lightMtx, mtxFloor, mtxShadow);
-		bgfx::setUniform(u_lightMtx, lightMtx);
 		uint32_t cached = bgfx::setTransform(mtxFloor);
 		for (uint32_t pass = 0; pass < 2; ++pass)
 		{
diff --git a/examples/23-vectordisplay/vectordisplay.cpp b/examples/23-vectordisplay/vectordisplay.cpp
index 46179aeb..42855023 100644
--- a/examples/23-vectordisplay/vectordisplay.cpp
+++ b/examples/23-vectordisplay/vectordisplay.cpp
@@ -210,8 +210,6 @@ void VectorDisplay::endFrame()
 
 	if (m_brightness > 0)
 	{
-		bgfx::setUniform(u_params, params);
-
 		bgfx::setTexture(0, s_texColor, m_sceneFrameBuffer);
 
 		int npasses = (int)(m_brightness * 4);
@@ -264,6 +262,8 @@ void VectorDisplay::endFrame()
 		}
 	}
 
+	bgfx::discard();
+
 	//now do last pass, combination of blur and normal buffer to screen
 	bgfx::setViewTransform(viewCounter, NULL, proj);
 	bgfx::setViewRect(viewCounter, 0, 0, m_screenWidth, m_screenHeight);
diff --git a/examples/common/nanovg/nanovg_bgfx.cpp b/examples/common/nanovg/nanovg_bgfx.cpp
index 8a7d83f4..263c1b31 100644
--- a/examples/common/nanovg/nanovg_bgfx.cpp
+++ b/examples/common/nanovg/nanovg_bgfx.cpp
@@ -667,7 +667,6 @@ namespace
 				);
 			bgfx::setVertexBuffer(&gl->tvb, paths[i].strokeOffset, paths[i].strokeCount);
 			bgfx::setTexture(0, gl->s_tex, gl->th);
-			bgfx::setTexture(0, gl->s_tex, gl->th);
 			bgfx::submit(gl->viewid, gl->prog);
 		}
 	}
diff --git a/src/bgfx.cpp b/src/bgfx.cpp
index a5aa5e67..cab1790b 100644
--- a/src/bgfx.cpp
+++ b/src/bgfx.cpp
@@ -1313,6 +1313,19 @@ namespace bgfx
 			);
 	}
 
+	const char* Context::getName(UniformHandle _handle) const
+	{
+		for (UniformHashMap::const_iterator it = m_uniformHashMap.begin(), itEnd = m_uniformHashMap.end(); it != itEnd; ++it)
+		{
+			if (it->second.idx == _handle.idx)
+			{
+				return it->first.c_str();
+			}
+		}
+
+		return NULL;
+	}
+
 	bool Context::renderFrame()
 	{
 		if (m_rendererInitialized
diff --git a/src/bgfx_p.h b/src/bgfx_p.h
index 26de034b..a25d1b83 100644
--- a/src/bgfx_p.h
+++ b/src/bgfx_p.h
@@ -2950,7 +2950,7 @@ namespace bgfx
 				, _handle.idx
 				, _width
 				, _height
-				, getName(TextureFormat::Enum(textureRef.m_format) )
+				, bgfx::getName(TextureFormat::Enum(textureRef.m_format) )
 				);
 
 			CommandBuffer& cmdbuf = getCommandBuffer(CommandBuffer::ResizeTexture);
@@ -3359,6 +3359,15 @@ namespace bgfx
 			BGFX_CHECK_HANDLE("setUniform", m_uniformHandle, _handle);
 			UniformRef& uniform = m_uniformRef[_handle.idx];
 			BX_CHECK(uniform.m_num >= _num, "Truncated uniform update. %d (max: %d)", _num, uniform.m_num);
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				BX_CHECK(m_uniformSet.end() == m_uniformSet.find(_handle.idx)
+					, "Uniform %d (%s) was already set for this draw call."
+					, _handle.idx
+					, getName(_handle)
+					);
+				m_uniformSet.insert(_handle.idx);
+			}
 			m_submit->writeUniform(uniform.m_type, _handle, _value, bx::uint16_min(uniform.m_num, _num) );
 		}
 
@@ -3446,6 +3455,10 @@ namespace bgfx
 		BGFX_API_FUNC(uint32_t submit(uint8_t _id, ProgramHandle _handle, int32_t _depth) )
 		{
 			BGFX_CHECK_HANDLE_INVALID_OK("submit", m_programHandle, _handle);
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				m_uniformSet.clear();
+			}
 			return m_submit->submit(_id, _handle, _depth);
 		}
 
@@ -3453,6 +3466,10 @@ namespace bgfx
 		{
 			BGFX_CHECK_HANDLE_INVALID_OK("submit", m_programHandle, _handle);
 			BGFX_CHECK_HANDLE("submit", m_vertexBufferHandle, _indirectHandle);
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				m_uniformSet.clear();
+			}
 			return m_submit->submit(_id, _handle, _indirectHandle, _start, _num, _depth);
 		}
 
@@ -3515,16 +3532,28 @@ namespace bgfx
 
 		BGFX_API_FUNC(uint32_t dispatch(uint8_t _id, ProgramHandle _handle, uint16_t _numX, uint16_t _numY, uint16_t _numZ, uint8_t _flags) )
 		{
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				m_uniformSet.clear();
+			}
 			return m_submit->dispatch(_id, _handle, _numX, _numY, _numZ, _flags);
 		}
 
 		BGFX_API_FUNC(uint32_t dispatch(uint8_t _id, ProgramHandle _handle, IndirectBufferHandle _indirectHandle, uint16_t _start, uint16_t _num, uint8_t _flags) )
 		{
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				m_uniformSet.clear();
+			}
 			return m_submit->dispatch(_id, _handle, _indirectHandle, _start, _num, _flags);
 		}
 
 		BGFX_API_FUNC(void discard() )
 		{
+			if (BX_ENABLED(BGFX_CONFIG_DEBUG_UNIFORM) )
+			{
+				m_uniformSet.clear();
+			}
 			m_submit->discard();
 		}
 
@@ -3535,6 +3564,7 @@ namespace bgfx
 		void freeAllHandles(Frame* _frame);
 		void frameNoRenderWait();
 		void swap();
+		const char* getName(UniformHandle _handle) const;
 
 		// render thread
 		bool renderFrame();
@@ -3676,6 +3706,8 @@ namespace bgfx
 
 		typedef stl::unordered_map<stl::string, UniformHandle> UniformHashMap;
 		UniformHashMap m_uniformHashMap;
+		typedef stl::unordered_set<uint16_t> UniformSet;
+		UniformSet m_uniformSet;
 		UniformRef m_uniformRef[BGFX_CONFIG_MAX_UNIFORMS];
 
 		ShaderRef m_shaderRef[BGFX_CONFIG_MAX_SHADERS];
diff --git a/src/config.h b/src/config.h
index 199fc144..550f9a3a 100644
--- a/src/config.h
+++ b/src/config.h
@@ -164,6 +164,11 @@
 #	define BGFX_CONFIG_DEBUG_MTL BGFX_CONFIG_DEBUG
 #endif // BGFX_CONFIG_DEBUG_MTL
 
+///
+#ifndef BGFX_CONFIG_DEBUG_UNIFORM
+#	define BGFX_CONFIG_DEBUG_UNIFORM BGFX_CONFIG_DEBUG
+#endif // BGFX_CONFIG_DEBUG_UNIFORM
+
 #ifndef BGFX_CONFIG_MULTITHREADED
 #	define BGFX_CONFIG_MULTITHREADED ( (!BGFX_CONFIG_RENDERER_NULL)&&(0 \
 						|| BX_PLATFORM_ANDROID \