diff --git a/postgis/lwgeom_functions_basic.c b/postgis/lwgeom_functions_basic.c
index 6606033ad79..a1d1ea7f2e2 100644
--- a/postgis/lwgeom_functions_basic.c
+++ b/postgis/lwgeom_functions_basic.c
@@ -1560,7 +1560,10 @@ Datum LWGEOM_makepoly(PG_FUNCTION_ARGS)
 		holes = lwalloc(sizeof(LWLINE *)*nholes);
 		for (i=0; i<nholes; i++)
 		{
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wsign-compare"
 			GSERIALIZED *g = (GSERIALIZED *)(ARR_DATA_PTR(array)+offset);
+#pragma GCC diagnostic pop
 			LWLINE *hole;
 			offset += INTALIGN(VARSIZE(g));
 			if ( gserialized_get_type(g) != LINETYPE )
diff --git a/postgis/lwgeom_geos.c b/postgis/lwgeom_geos.c
index 9a0be53d2ea..7454ce96053 100644
--- a/postgis/lwgeom_geos.c
+++ b/postgis/lwgeom_geos.c
@@ -420,7 +420,12 @@ Datum pgis_union_geometry_array(PG_FUNCTION_ARGS)
 
 	/* One geom, good geom? Return it */
 	if ( count == 1 && nelems == 1 )
+	{
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wsign-compare"
 		PG_RETURN_POINTER((GSERIALIZED *)(ARR_DATA_PTR(array)));
+#pragma GCC diagnostic pop
+	}
 
 	/* Ok, we really need GEOS now ;) */
 	initGEOS(lwpgnotice, lwgeom_geos_error);