Explicitly ignore a return value in gzwrite.c.
diff --git a/gzwrite.c b/gzwrite.c
index 1696692..b03097c 100644
--- a/gzwrite.c
+++ b/gzwrite.c
@@ -515,7 +515,7 @@
     }
 
     /* compress remaining data with requested flush */
-    gz_comp(state, flush);
+    (void)gz_comp(state, flush);
     return state->err;
 }