Fix some compiler warnings under MSVC.

FossilOrigin-Name: afdc82a99eba260aed8ae2cca4bcec629f384098

src/btree.c

@@ -1835,7 +1835,7 @@ int sqlite3BtreeOpen(
     if( rc!=SQLITE_OK ){
       goto btree_open_out;
     }
-    pBt->openFlags = flags;
+    pBt->openFlags = (u8)flags;
     pBt->db = db;
     sqlite3PagerSetBusyhandler(pBt->pPager, btreeInvokeBusyHandler, pBt);
     p->pBt = pBt;

src/main.c

@@ -1088,7 +1088,7 @@ int sqlite3_create_function_v2(
   void (*xFinal)(sqlite3_context*),
   void (*xDestroy)(void *)
 ){
-  int rc;
+  int rc = SQLITE_ERROR;
   FuncDestructor *pArg = 0;
   sqlite3_mutex_enter(db->mutex);
   if( xDestroy ){
@@ -1298,7 +1298,10 @@ int sqlite3WalDefaultHook(
 ** configured by this function.
 */
 int sqlite3_wal_autocheckpoint(sqlite3 *db, int nFrame){
-#ifndef SQLITE_OMIT_WAL
+#ifdef SQLITE_OMIT_WAL
+  UNUSED_PARAMETER(db);
+  UNUSED_PARAMETER(nFrame);
+#else
   if( nFrame>0 ){
     sqlite3_wal_hook(db, sqlite3WalDefaultHook, SQLITE_INT_TO_PTR(nFrame));
   }else{

src/mutex.h

@@ -63,8 +63,8 @@
 #define sqlite3_mutex_enter(X)
 #define sqlite3_mutex_try(X)      SQLITE_OK
 #define sqlite3_mutex_leave(X)
-#define sqlite3_mutex_held(X)     1
-#define sqlite3_mutex_notheld(X)  1
+#define sqlite3_mutex_held(X)     ((void)(X),1)
+#define sqlite3_mutex_notheld(X)  ((void)(X),1)
 #define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
 #define sqlite3MutexInit()        SQLITE_OK
 #define sqlite3MutexEnd()

src/os_win.c

@@ -2033,19 +2033,25 @@ static int winOpen(
   char zTmpname[MAX_PATH+1];     /* Buffer used to create temp filename */
 
   int rc = SQLITE_OK;            /* Function Return Code */
+#if !defined(NDEBUG) || SQLITE_OS_WINCE
   int eType = flags&0xFFFFFF00;  /* Type of file to open */
+#endif
 
   int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
   int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
   int isCreate     = (flags & SQLITE_OPEN_CREATE);
+#ifndef NDEBUG
   int isReadonly   = (flags & SQLITE_OPEN_READONLY);
+#endif
   int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
 
+#ifndef NDEBUG
   int isOpenJournal = (isCreate && (
         eType==SQLITE_OPEN_MASTER_JOURNAL 
      || eType==SQLITE_OPEN_MAIN_JOURNAL 
      || eType==SQLITE_OPEN_WAL
   ));
+#endif
 
   /* Check the following statements are true: 
   **

src/pcache1.c

@@ -814,7 +814,7 @@ int sqlite3PcacheReleaseMemory(int nReq){
   if( pcache1.pStart==0 ){
     PgHdr1 *p;
     pcache1EnterMutex();
-    while( (nReq<0 || nFree<nReq) && (p=pcache1.pLruTail) ){
+    while( (nReq<0 || nFree<nReq) && ((p=pcache1.pLruTail)!=0) ){
       nFree += pcache1MemSize(PGHDR1_TO_PAGE(p));
       pcache1PinPage(p);
       pcache1RemoveFromHash(p);

src/test_rtree.c

@@ -15,6 +15,9 @@
 
 #include <sqlite3.h>
 
+/* Solely for the UNUSED_PARAMETER() macro. */
+#include "sqliteInt.h"
+
 /* 
 ** Type used to cache parameter information for the "circle" r-tree geometry
 ** callback.
@@ -234,7 +237,12 @@ static int register_cube_geom(
   int objc,
   Tcl_Obj *CONST objv[]
 ){
-#ifdef SQLITE_ENABLE_RTREE
+#ifndef SQLITE_ENABLE_RTREE
+  UNUSED_PARAMETER(clientData);
+  UNUSED_PARAMETER(interp);
+  UNUSED_PARAMETER(objc);
+  UNUSED_PARAMETER(objv);
+#else
   extern int getDbPointer(Tcl_Interp*, const char*, sqlite3**);
   extern const char *sqlite3TestErrorName(int);
   sqlite3 *db;
@@ -257,7 +265,12 @@ static int register_circle_geom(
   int objc,
   Tcl_Obj *CONST objv[]
 ){
-#ifdef SQLITE_ENABLE_RTREE
+#ifndef SQLITE_ENABLE_RTREE
+  UNUSED_PARAMETER(clientData);
+  UNUSED_PARAMETER(interp);
+  UNUSED_PARAMETER(objc);
+  UNUSED_PARAMETER(objv);
+#else
   extern int getDbPointer(Tcl_Interp*, const char*, sqlite3**);
   extern const char *sqlite3TestErrorName(int);
   sqlite3 *db;

src/wal.c

@@ -2478,7 +2478,7 @@ int sqlite3WalFrames(
       return rc;
     }
   }
-  assert( pWal->szPage==szPage );
+  assert( (int)pWal->szPage==szPage );
 
   /* Write the log file. */
   for(p=pList; p; p=p->pDirty){