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diff --git a/lib/zip_close.c b/lib/zip_close.c
index 25ff4d5..e90e839 100644
--- a/lib/zip_close.c
+++ b/lib/zip_close.c
@@ -378,6 +378,7 @@
 
     needs_recompress = st.comp_method != ZIP_CM_ACTUAL(de->comp_method);
     needs_decompress = needs_recompress && (st.comp_method != ZIP_CM_STORE);
+    /* in these cases we can compute the CRC ourselves, so we do */
     needs_crc = (st.comp_method == ZIP_CM_STORE) || needs_decompress;
     needs_compress = needs_recompress && (de->comp_method != ZIP_CM_STORE);