diff --git a/src/gl/system/gl_interface.cpp b/src/gl/system/gl_interface.cpp
index 6e87eb95a..b7e10c1c8 100644
--- a/src/gl/system/gl_interface.cpp
+++ b/src/gl/system/gl_interface.cpp
@@ -265,7 +265,7 @@ void gl_LoadExtensions()
 
 			// Mesa implements shader storage only for fragment shaders.
 			// Just disable the feature there. The light buffer may just use a uniform buffer without any adverse effects.
-			int v;
+			int v = 0;
 			glGetIntegerv(GL_MAX_VERTEX_SHADER_STORAGE_BLOCKS, &v);
 			if (v == 0)
 				gl.flags &= ~RFL_SHADER_STORAGE_BUFFER;