Fixes the sqlite driver bug QTBUG-11904 (pointer aliasing)

Applying upstream sqlite patch from: http://www.sqlite.org/src/info/d6ae275122

Task-number: QTBUG-11904
Reviewed-by: Michael Goddard

1 files changed, 25 insertions, 22 deletions

diff --git a/src/3rdparty/sqlite/sqlite3.c b/src/3rdparty/sqlite/sqlite3.c
index 46d3dfc..27a8d18 100644
--- a/src/3rdparty/sqlite/sqlite3.c
+++ b/src/3rdparty/sqlite/sqlite3.c
@@ -48449,11 +48449,15 @@ SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
 #endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
 
 /*
-** Allocate space from a fixed size buffer.  Make *pp point to the
-** allocated space.  (Note:  pp is a char* rather than a void** to
-** work around the pointer aliasing rules of C.)  *pp should initially
-** be zero.  If *pp is not zero, that means that the space has already
-** been allocated and this routine is a noop.
+** Allocate space from a fixed size buffer and return a pointer to
+** that space.  If insufficient space is available, return NULL.
+**
+** The pBuf parameter is the initial value of a pointer which will
+** receive the new memory.  pBuf is normally NULL.  If pBuf is not
+** NULL, it means that memory space has already been allocated and that
+** this routine should not allocate any new memory.  When pBuf is not
+** NULL simply return pBuf.  Only allocate new memory space when pBuf
+** is NULL.
 **
 ** nByte is the number of bytes of space needed.
 **
@@ -48464,23 +48468,23 @@ SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
 ** to allocate.  If there is insufficient space in *ppFrom to satisfy the
 ** request, then increment *pnByte by the amount of the request.
 */
-static void allocSpace(
-  char *pp,            /* IN/OUT: Set *pp to point to allocated buffer */
+static void *allocSpace(
+  void *pBuf,          /* Where return pointer will be stored */
   int nByte,           /* Number of bytes to allocate */
   u8 **ppFrom,         /* IN/OUT: Allocate from *ppFrom */
   u8 *pEnd,            /* Pointer to 1 byte past the end of *ppFrom buffer */
   int *pnByte          /* If allocation cannot be made, increment *pnByte */
 ){
   assert( EIGHT_BYTE_ALIGNMENT(*ppFrom) );
-  if( (*(void**)pp)==0 ){
-    nByte = ROUND8(nByte);
-    if( &(*ppFrom)[nByte] <= pEnd ){
-      *(void**)pp = (void *)*ppFrom;
-      *ppFrom += nByte;
-    }else{
-      *pnByte += nByte;
-    }
+  if( pBuf ) return pBuf;
+  nByte = ROUND8(nByte);
+  if( &(*ppFrom)[nByte] <= pEnd ){
+    pBuf = (void*)*ppFrom;
+    *ppFrom += nByte;
+  }else{
+    *pnByte += nByte;
   }
+  return pBuf;
 }
 
 /*
@@ -48553,13 +48557,12 @@ SQLITE_PRIVATE void sqlite3VdbeMakeReady(
 
     do {
       nByte = 0;
-      allocSpace((char*)&p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte);
-      allocSpace((char*)&p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte);
-      allocSpace((char*)&p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte);
-      allocSpace((char*)&p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte);
-      allocSpace((char*)&p->apCsr, 
-                 nCursor*sizeof(VdbeCursor*), &zCsr, zEnd, &nByte
-      );
+      p->aMem = allocSpace(p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte);
+      p->aVar = allocSpace(p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte);
+      p->apArg = allocSpace(p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte);
+      p->azVar = allocSpace(p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte);
+      p->apCsr = allocSpace(p->apCsr, nCursor*sizeof(VdbeCursor*),
+                            &zCsr, zEnd, &nByte);
       if( nByte ){
         p->pFree = sqlite3DbMallocZero(db, nByte);
       }