Index: ext/misc/zipfile.c
==================================================================
--- ext/misc/zipfile.c
+++ ext/misc/zipfile.c
@@ -2059,13 +2059,15 @@
   nByte = ZIPFILE_LFH_FIXED_SZ + e.cds.nFile + 9;
   if( (rc = zipfileBufferGrow(&p->body, nByte)) ) goto zipfile_step_out;
   p->body.n += zipfileSerializeLFH(&e, &p->body.a[p->body.n]);
 
   /* Append the data to the body of the new archive */
-  if( (rc = zipfileBufferGrow(&p->body, nData)) ) goto zipfile_step_out;
-  memcpy(&p->body.a[p->body.n], aData, nData);
-  p->body.n += nData;
+  if( nData>0 ){
+    if( (rc = zipfileBufferGrow(&p->body, nData)) ) goto zipfile_step_out;
+    memcpy(&p->body.a[p->body.n], aData, nData);
+    p->body.n += nData;
+  }
 
   /* Append the CDS record to the directory of the new archive */
   nByte = ZIPFILE_CDS_FIXED_SZ + e.cds.nFile + 9;
   if( (rc = zipfileBufferGrow(&p->cds, nByte)) ) goto zipfile_step_out;
   p->cds.n += zipfileSerializeCDS(&e, &p->cds.a[p->cds.n]);

Index: ext/session/sqlite3session.c
==================================================================
--- ext/session/sqlite3session.c
+++ ext/session/sqlite3session.c
@@ -837,11 +837,11 @@
         if( eType==SQLITE_TEXT ){
           z = sqlite3_value_text(pVal);
         }else{
           z = sqlite3_value_blob(pVal);
         }
-        if( memcmp(a, z, n) ) return 0;
+        if( n>0 && memcmp(a, z, n) ) return 0;
         a += n;
       }
     }
   }