Index: src/vdbe.c
==================================================================
--- src/vdbe.c
+++ src/vdbe.c
@@ -241,16 +241,17 @@
 static void applyNumericAffinity(Mem *pRec, int bTryForInt){
   double rValue;
   i64 iValue;
   u8 enc = pRec->enc;
   if( (pRec->flags&MEM_Str)==0 ) return;
+  if( (pRec->flags&(MEM_Int|MEM_Real))!=0 ) return;
   if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
   if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
     pRec->u.i = iValue;
     pRec->flags |= MEM_Int;
   }else{
-    pRec->r = rValue;
+    pRec->u.r = rValue;
     pRec->flags |= MEM_Real;
     if( bTryForInt ) sqlite3VdbeIntegerAffinity(pRec);
   }
 }
 
@@ -327,17 +328,17 @@
 }
 
 /*
 ** pMem currently only holds a string type (or maybe a BLOB that we can
 ** interpret as a string if we want to).  Compute its corresponding
-** numeric type, if has one.  Set the pMem->r and pMem->u.i fields
+** numeric type, if has one.  Set the pMem->u.r and pMem->u.i fields
 ** accordingly.
 */
 static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
   assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
   assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
-  if( sqlite3AtoF(pMem->z, &pMem->r, pMem->n, pMem->enc)==0 ){
+  if( sqlite3AtoF(pMem->z, &pMem->u.r, pMem->n, pMem->enc)==0 ){
     return 0;
   }
   if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
     return MEM_Int;
   }
@@ -347,11 +348,11 @@
 /*
 ** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
 ** none.  
 **
 ** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
-** But it does set pMem->r and pMem->u.i appropriately.
+** But it does set pMem->u.r and pMem->u.i appropriately.
 */
 static u16 numericType(Mem *pMem){
   if( pMem->flags & (MEM_Int|MEM_Real) ){
     return pMem->flags & (MEM_Int|MEM_Real);
   }
@@ -457,11 +458,11 @@
     printf(" si:%lld", p->u.i);
   }else if( p->flags & MEM_Int ){
     printf(" i:%lld", p->u.i);
 #ifndef SQLITE_OMIT_FLOATING_POINT
   }else if( p->flags & MEM_Real ){
-    printf(" r:%g", p->r);
+    printf(" r:%g", p->u.r);
 #endif
   }else if( p->flags & MEM_RowSet ){
     printf(" (rowset)");
   }else{
     char zBuf[200];
@@ -1000,11 +1001,11 @@
 ** Write that value into register P2.
 */
 case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
   pOut->flags = MEM_Real;
   assert( !sqlite3IsNaN(*pOp->p4.pReal) );
-  pOut->r = *pOp->p4.pReal;
+  pOut->u.r = *pOp->p4.pReal;
   break;
 }
 #endif
 
 /* Opcode: String8 * P2 * P4 *
@@ -1477,11 +1478,11 @@
     MemSetTypeFlag(pOut, MEM_Int);
 #else
     if( sqlite3IsNaN(rB) ){
       goto arithmetic_result_is_null;
     }
-    pOut->r = rB;
+    pOut->u.r = rB;
     MemSetTypeFlag(pOut, MEM_Real);
     if( ((type1|type2)&MEM_Real)==0 && !bIntint ){
       sqlite3VdbeIntegerAffinity(pOut);
     }
 #endif
@@ -3570,20 +3571,20 @@
       ** is 4.9 and the integer approximation 5:
       **
       **        (x >  4.9)    ->     (x >= 5)
       **        (x <= 4.9)    ->     (x <  5)
       */
-      if( pIn3->r<(double)iKey ){
+      if( pIn3->u.r<(double)iKey ){
         assert( OP_SeekGE==(OP_SeekGT-1) );
         assert( OP_SeekLT==(OP_SeekLE-1) );
         assert( (OP_SeekLE & 0x0001)==(OP_SeekGT & 0x0001) );
         if( (oc & 0x0001)==(OP_SeekGT & 0x0001) ) oc--;
       }
 
       /* If the approximation iKey is smaller than the actual real search
       ** term, substitute <= for < and > for >=.  */
-      else if( pIn3->r>(double)iKey ){
+      else if( pIn3->u.r>(double)iKey ){
         assert( OP_SeekLE==(OP_SeekLT+1) );
         assert( OP_SeekGT==(OP_SeekGE+1) );
         assert( (OP_SeekLT & 0x0001)==(OP_SeekGE & 0x0001) );
         if( (oc & 0x0001)==(OP_SeekLT & 0x0001) ) oc++;
       }

Index: src/vdbeInt.h
==================================================================
--- src/vdbeInt.h
+++ src/vdbeInt.h
@@ -159,24 +159,24 @@
 ** Internally, the vdbe manipulates nearly all SQL values as Mem
 ** structures. Each Mem struct may cache multiple representations (string,
 ** integer etc.) of the same value.
 */
 struct Mem {
-  union {
+  union MemValue {
+    double r;           /* Real value used when MEM_Realis set in flags */
     i64 i;              /* Integer value used when MEM_Int is set in flags */
     int nZero;          /* Used when bit MEM_Zero is set in flags */
     FuncDef *pDef;      /* Used only when flags==MEM_Agg */
     RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
     VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
   } u;
   u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
   u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
   int n;              /* Number of characters in string value, excluding '\0' */
-  double r;           /* Real value */
   char *z;            /* String or BLOB value */
-  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
   /* ShallowCopy only needs to copy the information above */
+  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
   sqlite3 *db;        /* The associated database connection */
   void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
 #ifdef SQLITE_DEBUG
   Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
   void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */

Index: src/vdbeapi.c
==================================================================
--- src/vdbeapi.c
+++ src/vdbeapi.c
@@ -805,11 +805,10 @@
     = {
         /* .u          = */ {0},
         /* .flags      = */ MEM_Null,
         /* .enc        = */ 0,
         /* .n          = */ 0,
-        /* .r          = */ (double)0,
         /* .z          = */ 0,
         /* .zMalloc    = */ 0,
         /* .db         = */ 0,
         /* .xDel       = */ 0,
 #ifdef SQLITE_DEBUG
@@ -1270,11 +1269,11 @@
     case SQLITE_INTEGER: {
       rc = sqlite3_bind_int64(pStmt, i, pValue->u.i);
       break;
     }
     case SQLITE_FLOAT: {
-      rc = sqlite3_bind_double(pStmt, i, pValue->r);
+      rc = sqlite3_bind_double(pStmt, i, pValue->u.r);
       break;
     }
     case SQLITE_BLOB: {
       if( pValue->flags & MEM_Zero ){
         rc = sqlite3_bind_zeroblob(pStmt, i, pValue->u.nZero);

Index: src/vdbeaux.c
==================================================================
--- src/vdbeaux.c
+++ src/vdbeaux.c
@@ -1074,11 +1074,11 @@
       if( pMem->flags & MEM_Str ){
         zP4 = pMem->z;
       }else if( pMem->flags & MEM_Int ){
         sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
       }else if( pMem->flags & MEM_Real ){
-        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
+        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->u.r);
       }else if( pMem->flags & MEM_Null ){
         sqlite3_snprintf(nTemp, zTemp, "NULL");
       }else{
         assert( pMem->flags & MEM_Blob );
         zP4 = "(blob)";
@@ -2947,12 +2947,12 @@
   /* Integer and Real */
   if( serial_type<=7 && serial_type>0 ){
     u64 v;
     u32 i;
     if( serial_type==7 ){
-      assert( sizeof(v)==sizeof(pMem->r) );
-      memcpy(&v, &pMem->r, sizeof(v));
+      assert( sizeof(v)==sizeof(pMem->u.r) );
+      memcpy(&v, &pMem->u.r, sizeof(v));
       swapMixedEndianFloat(v);
     }else{
       v = pMem->u.i;
     }
     len = i = sqlite3VdbeSerialTypeLen(serial_type);
@@ -3018,14 +3018,14 @@
     static const double r1 = 1.0;
     u64 t2 = t1;
     swapMixedEndianFloat(t2);
     assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
 #endif
-    assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
+    assert( sizeof(x)==8 && sizeof(pMem->u.r)==8 );
     swapMixedEndianFloat(x);
-    memcpy(&pMem->r, &x, sizeof(x));
-    pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
+    memcpy(&pMem->u.r, &x, sizeof(x));
+    pMem->flags = sqlite3IsNaN(pMem->u.r) ? MEM_Null : MEM_Real;
   }
   return 8;
 }
 u32 sqlite3VdbeSerialGet(
   const unsigned char *buf,     /* Buffer to deserialize from */
@@ -3366,18 +3366,18 @@
       if( pMem1->u.i < pMem2->u.i ) return -1;
       if( pMem1->u.i > pMem2->u.i ) return 1;
       return 0;
     }
     if( (f1&MEM_Real)!=0 ){
-      r1 = pMem1->r;
+      r1 = pMem1->u.r;
     }else if( (f1&MEM_Int)!=0 ){
       r1 = (double)pMem1->u.i;
     }else{
       return 1;
     }
     if( (f2&MEM_Real)!=0 ){
-      r2 = pMem2->r;
+      r2 = pMem2->u.r;
     }else if( (f2&MEM_Int)!=0 ){
       r2 = (double)pMem2->u.i;
     }else{
       return -1;
     }
@@ -3534,13 +3534,13 @@
       }else if( serial_type==0 ){
         rc = -1;
       }else if( serial_type==7 ){
         double rhs = (double)pRhs->u.i;
         sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
-        if( mem1.r<rhs ){
+        if( mem1.u.r<rhs ){
           rc = -1;
-        }else if( mem1.r>rhs ){
+        }else if( mem1.u.r>rhs ){
           rc = +1;
         }
       }else{
         i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
         i64 rhs = pRhs->u.i;
@@ -3558,15 +3558,15 @@
       if( serial_type>=12 ){
         rc = +1;
       }else if( serial_type==0 ){
         rc = -1;
       }else{
-        double rhs = pRhs->r;
+        double rhs = pRhs->u.r;
         double lhs;
         sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
         if( serial_type==7 ){
-          lhs = mem1.r;
+          lhs = mem1.u.r;
         }else{
           lhs = (double)mem1.u.i;
         }
         if( lhs<rhs ){
           rc = -1;

Index: src/vdbemem.c
==================================================================
--- src/vdbemem.c
+++ src/vdbemem.c
@@ -29,10 +29,13 @@
   /* If MEM_Dyn is set then Mem.xDel!=0.  
   ** Mem.xDel is might not be initialized if MEM_Dyn is clear.
   */
   assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );
 
+  /* Cannot be both MEM_Int and MEM_Real at the same time */
+  assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );
+
   /* If p holds a string or blob, the Mem.z must point to exactly
   ** one of the following:
   **
   **   (1) Memory in Mem.zMalloc and managed by the Mem object
   **   (2) Memory to be freed using Mem.xDel
@@ -262,11 +265,11 @@
   */
   if( fg & MEM_Int ){
     sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
   }else{
     assert( fg & MEM_Real );
-    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
+    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->u.r);
   }
   pMem->n = sqlite3Strlen30(pMem->z);
   pMem->enc = SQLITE_UTF8;
   pMem->flags |= MEM_Str|MEM_Term;
   if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
@@ -419,11 +422,11 @@
   assert( EIGHT_BYTE_ALIGNMENT(pMem) );
   flags = pMem->flags;
   if( flags & MEM_Int ){
     return pMem->u.i;
   }else if( flags & MEM_Real ){
-    return doubleToInt64(pMem->r);
+    return doubleToInt64(pMem->u.r);
   }else if( flags & (MEM_Str|MEM_Blob) ){
     i64 value = 0;
     assert( pMem->z || pMem->n==0 );
     sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
     return value;
@@ -440,11 +443,11 @@
 */
 double sqlite3VdbeRealValue(Mem *pMem){
   assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
   assert( EIGHT_BYTE_ALIGNMENT(pMem) );
   if( pMem->flags & MEM_Real ){
-    return pMem->r;
+    return pMem->u.r;
   }else if( pMem->flags & MEM_Int ){
     return (double)pMem->u.i;
   }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
     /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
     double val = (double)0;
@@ -459,16 +462,17 @@
 /*
 ** The MEM structure is already a MEM_Real.  Try to also make it a
 ** MEM_Int if we can.
 */
 void sqlite3VdbeIntegerAffinity(Mem *pMem){
+  i64 ix;
   assert( pMem->flags & MEM_Real );
   assert( (pMem->flags & MEM_RowSet)==0 );
   assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
   assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-  pMem->u.i = doubleToInt64(pMem->r);
+  ix = doubleToInt64(pMem->u.r);
 
   /* Only mark the value as an integer if
   **
   **    (1) the round-trip conversion real->int->real is a no-op, and
   **    (2) The integer is neither the largest nor the smallest
@@ -476,15 +480,13 @@
   **
   ** The second and third terms in the following conditional enforces
   ** the second condition under the assumption that addition overflow causes
   ** values to wrap around.
   */
-  if( pMem->r==(double)pMem->u.i
-   && pMem->u.i>SMALLEST_INT64
-   && pMem->u.i<LARGEST_INT64
-  ){
-    pMem->flags |= MEM_Int;
+  if( pMem->u.r==ix && ix>SMALLEST_INT64 && ix<LARGEST_INT64 ){
+    pMem->u.i = ix;
+    MemSetTypeFlag(pMem, MEM_Int);
   }
 }
 
 /*
 ** Convert pMem to type integer.  Invalidate any prior representations.
@@ -505,11 +507,11 @@
 */
 int sqlite3VdbeMemRealify(Mem *pMem){
   assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
   assert( EIGHT_BYTE_ALIGNMENT(pMem) );
 
-  pMem->r = sqlite3VdbeRealValue(pMem);
+  pMem->u.r = sqlite3VdbeRealValue(pMem);
   MemSetTypeFlag(pMem, MEM_Real);
   return SQLITE_OK;
 }
 
 /*
@@ -525,11 +527,11 @@
     assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
     assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
     if( 0==sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc) ){
       MemSetTypeFlag(pMem, MEM_Int);
     }else{
-      pMem->r = sqlite3VdbeRealValue(pMem);
+      pMem->u.r = sqlite3VdbeRealValue(pMem);
       MemSetTypeFlag(pMem, MEM_Real);
       sqlite3VdbeIntegerAffinity(pMem);
     }
   }
   assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
@@ -661,11 +663,11 @@
 ** manifest type REAL.
 */
 void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
   sqlite3VdbeMemSetNull(pMem);
   if( !sqlite3IsNaN(val) ){
-    pMem->r = val;
+    pMem->u.r = val;
     pMem->flags = MEM_Real;
   }
 }
 #endif
 
@@ -1166,18 +1168,18 @@
     /* This branch happens for multiple negative signs.  Ex: -(-5) */
     if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) 
      && pVal!=0
     ){
       sqlite3VdbeMemNumerify(pVal);
-      if( pVal->u.i==SMALLEST_INT64 ){
-        pVal->flags &= ~MEM_Int;
-        pVal->flags |= MEM_Real;
-        pVal->r = (double)SMALLEST_INT64;
+      if( pVal->flags & MEM_Real ){
+        pVal->u.r = -pVal->u.r;
+      }else if( pVal->u.i==SMALLEST_INT64 ){
+        pVal->u.r = -(double)SMALLEST_INT64;
+        MemSetTypeFlag(pVal, MEM_Real);
       }else{
         pVal->u.i = -pVal->u.i;
       }
-      pVal->r = -pVal->r;
       sqlite3ValueApplyAffinity(pVal, affinity, enc);
     }
   }else if( op==TK_NULL ){
     pVal = valueNew(db, pCtx);
     if( pVal==0 ) goto no_mem;

Index: src/vdbetrace.c
==================================================================
--- src/vdbetrace.c
+++ src/vdbetrace.c
@@ -125,11 +125,11 @@
       if( pVar->flags & MEM_Null ){
         sqlite3StrAccumAppend(&out, "NULL", 4);
       }else if( pVar->flags & MEM_Int ){
         sqlite3XPrintf(&out, 0, "%lld", pVar->u.i);
       }else if( pVar->flags & MEM_Real ){
-        sqlite3XPrintf(&out, 0, "%!.15g", pVar->r);
+        sqlite3XPrintf(&out, 0, "%!.15g", pVar->u.r);
       }else if( pVar->flags & MEM_Str ){
         int nOut;  /* Number of bytes of the string text to include in output */
 #ifndef SQLITE_OMIT_UTF16
         u8 enc = ENC(db);
         Mem utf8;