Fix a faulty assert() in the sqlite3VdbeMemExpandBlob() routine.

FossilOrigin-Name: df58774e994bd306b1a2e1f259e7e4408f01c5b1dc104673698168bbf8a63ce5

manifest

@@ -1,5 +1,5 @@
-C Fix\stwo\sassert()\sstatements\sin\sfts5\sthat\sare\sonly\strue\sif\sthe\sdatabase\sis\snot\scorrupt.
-D 2019-04-06T15:38:46.026
+C Fix\sa\sfaulty\sassert()\sin\sthe\ssqlite3VdbeMemExpandBlob()\sroutine.
+D 2019-04-07T18:04:57.144
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -591,11 +591,11 @@ F src/util.c 276d937c78e9d06f84db469d394573a5c533fb8d0e11a5114c575a99f3dabfa5
 F src/vacuum.c 72690ccb6877a88f8473a893cf9f6d7592236f3eebfebfa840b19c708acde574
 F src/vdbe.c 711ef421b3bb3db3b2476067b2dc3c71ef5844d9b1a723026578f89f6da621e8
 F src/vdbe.h 712bca562eaed1c25506b9faf9680bdc75fc42e2f4a1cd518d883fa79c7a4237
-F src/vdbeInt.h d0c78ec6ba57e438164c46ee8129ee00ccd898c472b27e325c9758eda533e37e
+F src/vdbeInt.h 2c12704db9740c8e899786ecfc7a5797a9d067563496eb1b6ed03c592d7b8d90
 F src/vdbeapi.c a6e462bd7853e272cf614d6fbda7f3f20c89a2d255805855b32895a5983ddcec
 F src/vdbeaux.c 7aa412e7e56eb53649d87766f3064994a31991ee2b2716bf8c3129fa15cc7653
 F src/vdbeblob.c f5c70f973ea3a9e915d1693278a5f890dc78594300cf4d54e64f2b0917c94191
-F src/vdbemem.c 6d67403debf6eb2b0c8d956ea09bb0ad79b4b45af2a7e2b2736894e703ae3286
+F src/vdbemem.c 340bf04f095d55c26299849a1ffc356c24906e12fe618cbbc0d919d290457c06
 F src/vdbesort.c 90aad5a92608f2dd771c96749beabdb562c9d881131a860a7a5bccf66dc3be7f
 F src/vdbetrace.c 79d6dbbc479267b255a7de8080eee6e729928a0ef93ed9b0bfa5618875b48392
 F src/vtab.c 2462b7d6fd72b0b916477f5ef210ee49ab58cec195483ebdac0c8c5e3ec42cab
@@ -996,7 +996,7 @@ F test/fuzzdata4.db b502c7d5498261715812dd8b3c2005bad08b3a26e6489414bd13926cd3e4
 F test/fuzzdata5.db e35f64af17ec48926481cfaf3b3855e436bd40d1cfe2d59a9474cb4b748a52a5
 F test/fuzzdata6.db 92a80e4afc172c24f662a10a612d188fb272de4a9bd19e017927c95f737de6d7
 F test/fuzzdata7.db f46c9a5698c1ca75ca6280c7c879a3f46dc82fe4b1ce246827496b806488952d
-F test/fuzzdata8.db 9dcffb6ca959e466e3da7d76f992d877dfc0b302d316554a786d320af97a6dd2
+F test/fuzzdata8.db 5f12b6a8579e89616da9bd6dede1f38748eb04a1265f0b89117274f44d76b227
 F test/fuzzer1.test 3d4c4b7e547aba5e5511a2991e3e3d07166cfbb8
 F test/fuzzer2.test a85ef814ce071293bce1ad8dffa217cbbaad4c14
 F test/fuzzerfault.test 8792cd77fd5bce765b05d0c8e01b9edcf8af8536
@@ -1814,7 +1814,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
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-U dan
-Z 46513b26d98c69e39b038280492e0af2
+P edb095a9a679c8c702abd0a487e55ed4b09110b54bcd7d5275020576f2713a39
+R b1b831f46bb9a54c2be05d85e4d76596
+U drh
+Z 39681fb72b93d8847d98f82bd386460b

manifest.uuid

@@ -1 +1 @@
-edb095a9a679c8c702abd0a487e55ed4b09110b54bcd7d5275020576f2713a39
+df58774e994bd306b1a2e1f259e7e4408f01c5b1dc104673698168bbf8a63ce5

src/vdbeInt.h

@@ -282,6 +282,12 @@ struct sqlite3_value {
 #define MemSetTypeFlag(p, f) \
    ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
 
+/*
+** True if Mem X is a NULL-nochng type.
+*/
+#define MemNullNochng(X) \
+  ((X)->flags==(MEM_Null|MEM_Zero) && (X)->n==0 && (X)->u.nZero==0)
+
 /*
 ** Return true if a memory cell is not marked as invalid.  This macro
 ** is for use inside assert() statements only.

src/vdbemem.c

@@ -192,7 +192,10 @@ SQLITE_NOINLINE int sqlite3VdbeMemGrow(Mem *pMem, int n, int bPreserve){
 
   /* If the bPreserve flag is set to true, then the memory cell must already
   ** contain a valid string or blob value.  */
-  assert( bPreserve==0 || pMem->flags&(MEM_Blob|MEM_Str) );
+  assert( bPreserve==0 
+       || pMem->flags&(MEM_Blob|MEM_Str)
+       || MemNullNochng(pMem)
+  );
   testcase( bPreserve && pMem->z==0 );
 
   assert( pMem->szMalloc==0
@@ -298,7 +301,8 @@ int sqlite3VdbeMemMakeWriteable(Mem *pMem){
 int sqlite3VdbeMemExpandBlob(Mem *pMem){
   int nByte;
   assert( pMem->flags & MEM_Zero );
-  assert( pMem->flags&MEM_Blob );
+  assert( (pMem->flags&MEM_Blob)!=0 || MemNullNochng(pMem) );
+  testcase( MemNullNochng(pMem) )
   assert( !sqlite3VdbeMemIsRowSet(pMem) );
   assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );