diff --git a/GL/draw.c b/GL/draw.c
index aabfb8f..b6acd16 100644
--- a/GL/draw.c
+++ b/GL/draw.c
@@ -780,11 +780,12 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
     /* Make room in the list buffer */
     GLsizei spaceNeeded = (mode == GL_POLYGON || mode == GL_TRIANGLE_FAN) ? ((count - 2) * 3) : count;
     ClipVertex* start = aligned_vector_extend(&activeList->vector, spaceNeeded + 1);
-    uint32_t startOffset = start - (ClipVertex*) activeList->vector.data;
 
     /* Store a pointer to the header for later */
     PVRHeader* header = (PVRHeader*) start++;
 
+    uint32_t startOffset = start - (ClipVertex*) activeList->vector.data;
+
     profiler_checkpoint("allocate");
 
     generate(start, mode, first, count, (GLubyte*) indices, type, doTexture, doMultitexture, doLighting);