diff --git a/src/OpenGL/libGLESv2/Program.cpp b/src/OpenGL/libGLESv2/Program.cpp
index 957f83a..af3b21d 100644
--- a/src/OpenGL/libGLESv2/Program.cpp
+++ b/src/OpenGL/libGLESv2/Program.cpp
@@ -346,7 +346,7 @@
 
 	GLint Program::getUniformLocation(const std::string &name) const
 	{
-		int subscript = GL_INVALID_INDEX;
+		unsigned int subscript = GL_INVALID_INDEX;
 		std::string baseName = es2::ParseUniformName(name, &subscript);
 
 		size_t numUniforms = uniformIndex.size();
@@ -368,7 +368,7 @@
 
 	GLuint Program::getUniformIndex(const std::string &name) const
 	{
-		int subscript = GL_INVALID_INDEX;
+		unsigned int subscript = GL_INVALID_INDEX;
 		std::string baseName = es2::ParseUniformName(name, &subscript);
 
 		// The app is not allowed to specify array indices other than 0 for arrays of basic types
@@ -429,7 +429,7 @@
 
 	GLuint Program::getUniformBlockIndex(const std::string &name) const
 	{
-		int subscript = GL_INVALID_INDEX;
+		unsigned int subscript = GL_INVALID_INDEX;
 		std::string baseName = es2::ParseUniformName(name, &subscript);
 
 		size_t numUniformBlocks = getActiveUniformBlockCount();
@@ -1366,7 +1366,7 @@
 
 		for(const std::string &indexedTfVaryingName : transformFeedbackVaryings)
 		{
-			int subscript = GL_INVALID_INDEX;
+			unsigned int subscript = GL_INVALID_INDEX;
 			std::string tfVaryingName = es2::ParseUniformName(indexedTfVaryingName, &subscript);
 			bool hasSubscript = (subscript != GL_INVALID_INDEX);
 
diff --git a/src/OpenGL/libGLESv2/utilities.cpp b/src/OpenGL/libGLESv2/utilities.cpp
index 73a5a4e..70ff932 100644
--- a/src/OpenGL/libGLESv2/utilities.cpp
+++ b/src/OpenGL/libGLESv2/utilities.cpp
@@ -1180,7 +1180,7 @@
 		return false;
 	}
 
-	std::string ParseUniformName(const std::string &name, int *outSubscript)
+	std::string ParseUniformName(const std::string &name, unsigned int *outSubscript)
 	{
 		// Strip any trailing array operator and retrieve the subscript
 		size_t open = name.find_last_of('[');
diff --git a/src/OpenGL/libGLESv2/utilities.h b/src/OpenGL/libGLESv2/utilities.h
index 2b904e0..6a4d408 100644
--- a/src/OpenGL/libGLESv2/utilities.h
+++ b/src/OpenGL/libGLESv2/utilities.h
@@ -60,7 +60,7 @@
 
 	// Parse the base uniform name and array index.  Returns the base name of the uniform. outSubscript is
 	// set to GL_INVALID_INDEX if the provided name is not an array or the array index is invalid.
-	std::string ParseUniformName(const std::string &name, int *outSubscript);
+	std::string ParseUniformName(const std::string &name, unsigned int *outSubscript);
 }
 
 namespace es2sw