diff --git a/Makefile.msc b/Makefile.msc
index 5330f8962f..d3a40a811b 100644
--- a/Makefile.msc
+++ b/Makefile.msc
@@ -480,8 +480,8 @@ RCC = $(RCC) -DSQLITE_DEBUG
 !ENDIF
 
 !IF $(DEBUG)>4
-TCC = $(TCC) -DSQLITE_DEBUG_OS_TRACE=1
-RCC = $(RCC) -DSQLITE_DEBUG_OS_TRACE=1
+TCC = $(TCC) -DSQLITE_DEBUG_OS_TRACE=1 -DSQLITE_FORCE_OS_TRACE=1
+RCC = $(RCC) -DSQLITE_DEBUG_OS_TRACE=1 -DSQLITE_FORCE_OS_TRACE=1
 !ENDIF
 
 !IF $(DEBUG)>5
@@ -1158,8 +1158,8 @@ mptester.exe:	$(TOP)\mptest\mptest.c $(SHELL_CORE_DEP) $(LIBRESOBJS) sqlite3.h
 	$(LTLINK) $(SHELL_COMPILE_OPTS) $(TOP)\mptest\mptest.c \
 		/link $(LTLINKOPTS) $(LTLIBPATHS) $(SHELL_LINK_OPTS) $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)
 
-MPTEST1 = mptester mptest.db $(TOP)/mptest/crash01.test --repeat 20
-MPTEST2 = mptester mptest.db $(TOP)/mptest/multiwrite01.test --repeat 20
+MPTEST1 = mptester mptest.db $(TOP)\mptest\crash01.test --repeat 20
+MPTEST2 = mptester mptest.db $(TOP)\mptest\multiwrite01.test --repeat 20
 
 mptest:	mptester.exe
 	del /Q mptest.db 2>NUL
diff --git a/manifest b/manifest
index 63d5d9eccf..5d40a858f2 100644
--- a/manifest
+++ b/manifest
@@ -1,9 +1,9 @@
-C On\swindows,\sflush\sthe\smapping\sview\swhen\ssyncing\scontent\sto\sdisk.
-D 2015-03-31T19:40:05.313
+C Improved\stracing\sand\sdebugging\ssupport\son\swindows.
+D 2015-04-01T01:26:12.429
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 00d12636df7a5b08af09116bcd6c7bfd49b8b3b4
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
-F Makefile.msc a8d817fa486d8c88dfbd19ae6a6567d9d350de39
+F Makefile.msc c3744ee851d76d2be0ff247f5a89a74c88f2ece2
 F Makefile.vxworks e1b65dea203f054e71653415bd8f96dcaed47858
 F README.md d58e3bebc0a4145e0f2a87994015fdb575a8e866
 F VERSION 319eb1ced4b4d17a67730f2b7b85f15c1346cb60
@@ -160,7 +160,7 @@ F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
 F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
 F mptest/crash01.test 61e61469e257df0850df4293d7d4d6c2af301421
 F mptest/crash02.subtest f4ef05adcd15d60e5d2bd654204f2c008b519df8
-F mptest/mptest.c dae6de83eddac3ef97fc4111632f6066760f939a
+F mptest/mptest.c fca59f0a922e03f95ed17c44b1515ed37a841c81
 F mptest/multiwrite01.test dab5c5f8f9534971efce679152c5146da265222d
 F spec.template 86a4a43b99ebb3e75e6b9a735d5fd293a24e90ca
 F sqlite.pc.in 42b7bf0d02e08b9e77734a47798d1a55a9e0716b
@@ -195,7 +195,7 @@ F src/journal.c b4124532212b6952f42eb2c12fa3c25701d8ba8d
 F src/legacy.c ba1863ea58c4c840335a84ec276fc2b25e22bc4e
 F src/lempar.c 7274c97d24bb46631e504332ccd3bd1b37841770
 F src/loadext.c 86bd4e2fccd520b748cba52492ab60c4a770f660
-F src/main.c 40e333960d53f7d50ee8ce09d40431c87ea653f2
+F src/main.c cc3ac7793d38cb3e7e185edbc1f53ca311621a3a
 F src/malloc.c 6a370b83d54e4bbf6f94021221c2a311cff26a18
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c abe6ee469b6c5a35c7f22bfeb9c9bac664a1c987
@@ -212,10 +212,10 @@ F src/mutex_w32.c 61660ada28d8308ad190f444c2170c4f2a590c2f
 F src/notify.c 9711a7575036f0d3040ba61bc6e217f13a9888e7
 F src/os.c 8fd25588eeba74068d41102d26810e216999b6c8
 F src/os.h 3e57a24e2794a94d3cf2342c6d9a884888cd96bf
-F src/os_common.h 92815ed65f805560b66166e3583470ff94478f04
+F src/os_common.h 4fccbf81ef328c9ac231211de379e753b1365313
 F src/os_setup.h c9d4553b5aaa6f73391448b265b89bed0b890faa
 F src/os_unix.c a4dadbc2da41599e99093e91e276c38c17a73b89
-F src/os_win.c 03d27be3a20048ef52a648d5f0a15f5edda9f2a3
+F src/os_win.c eeb317cd504f39ef2dbcf50eb228bc9dd301d024
 F src/os_win.h eb7a47aa17b26b77eb97e4823f20a00b8bda12ca
 F src/pager.c 4120a49ecd37697e28f5ed807f470b9c0b88410c
 F src/pager.h c3476e7c89cdf1c6914e50a11f3714e30b4e0a77
@@ -226,7 +226,7 @@ F src/pcache1.c 69d137620a305f814398bd29a0c998038c0695e9
 F src/pragma.c ac4f3f856b4234e85f55b0f069698a4766011100
 F src/pragma.h 09c89bca58e9a44de2116cc8272b8d454657129f
 F src/prepare.c 173a5a499138451b2561614ecb87d78f9f4644b9
-F src/printf.c 8da9a2687a396daa19860f4dc90975d319304744
+F src/printf.c 8fff88d299f00e114e1a5afc90aa4c8744bf8877
 F src/random.c ba2679f80ec82c4190062d756f22d0c358180696
 F src/resolve.c f4d79e31ffa5820c2e3d1740baa5e9b190425f2b
 F src/rowset.c eccf6af6d620aaa4579bd3b72c1b6395d9e9fa1e
@@ -235,7 +235,7 @@ F src/shell.c 84a1593bd86aaa14f4da8a8f9b16fbc239d262aa
 F src/sqlite.h.in 278602140d49575e8708e643161f4263e428a02a
 F src/sqlite3.rc 992c9f5fb8285ae285d6be28240a7e8d3a7f2bad
 F src/sqlite3ext.h 17d487c3c91b0b8c584a32fbeb393f6f795eea7d
-F src/sqliteInt.h d02d2b85cb02a38bc442cf9302ec8209baf6771d
+F src/sqliteInt.h 75e86ef580cae23a36c4acfc2f664f528f8aee91
 F src/sqliteLimit.h 216557999cb45f2e3578ed53ebefe228d779cb46
 F src/status.c f266ad8a2892d659b74f0f50cb6a88b6e7c12179
 F src/table.c e7a09215315a978057fb42c640f890160dbcc45e
@@ -1248,8 +1248,8 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P ea697e6d9ff1f4d77774589a02ba4a18feafbf03 45acf6a85150839d591316418dad59ae20ce3aa4
-R 00dcdcdf447a25afe74cb2a2ac195e0b
-T +closed 45acf6a85150839d591316418dad59ae20ce3aa4
+P a828e73dc1ae50189bdf73f60caeb7308738ad7a fa7916b67efbc44e6f115bb0d32d8b92fd0acf3c
+R 7fa87c853794881c54344291c71c3804
+T +closed fa7916b67efbc44e6f115bb0d32d8b92fd0acf3c
 U drh
-Z e131d4f6392434ebe038899ef79bd289
+Z ed8d955d5896e461a30bebb3cc60c312
diff --git a/manifest.uuid b/manifest.uuid
index 6301587c11..d53ff492b9 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a828e73dc1ae50189bdf73f60caeb7308738ad7a
\ No newline at end of file
+5c965a71b957fdb0310ac1af9bf2fc3b418af668
\ No newline at end of file
diff --git a/mptest/mptest.c b/mptest/mptest.c
index 52ff6a4c83..f81ffb5ca0 100644
--- a/mptest/mptest.c
+++ b/mptest/mptest.c
@@ -53,6 +53,13 @@
 # define GETPID getpid
 #endif
 
+/* The directory separator character(s) */
+#if defined(_WIN32)
+# define isDirSep(c) (((c) == '/') || ((c) == '\\'))
+#else
+# define isDirSep(c) ((c) == '/')
+#endif
+
 /* Mark a parameter as unused to suppress compiler warnings */
 #define UNUSED_PARAMETER(x)  (void)x
 
@@ -824,7 +831,7 @@ static void waitForClient(int iClient, int iTimeout, char *zErrPrefix){
 */
 static char *filenameTail(char *z){
   int i, j;
-  for(i=j=0; z[i]; i++) if( z[i]=='/' ) j = i+1;
+  for(i=j=0; z[i]; i++) if( isDirSep(z[i]) ) j = i+1;
   return z+j;
 }
 
@@ -1021,9 +1028,9 @@ static void runScript(
       char *zNewFile, *zNewScript;
       char *zToDel = 0;
       zNewFile = azArg[0];
-      if( zNewFile[0]!='/' ){
+      if( !isDirSep(zNewFile[0]) ){
         int k;
-        for(k=(int)strlen(zFilename)-1; k>=0 && zFilename[k]!='/'; k--){}
+        for(k=(int)strlen(zFilename)-1; k>=0 && !isDirSep(zFilename[k]); k--){}
         if( k>0 ){
           zNewFile = zToDel = sqlite3_mprintf("%.*s/%s", k,zFilename,zNewFile);
         }
@@ -1231,7 +1238,7 @@ static void usage(const char *argv0){
   int i;
   const char *zTail = argv0;
   for(i=0; argv0[i]; i++){
-    if( argv0[i]=='/' ) zTail = argv0+i+1;
+    if( isDirSep(argv0[i]) ) zTail = argv0+i+1;
   }
   fprintf(stderr,"Usage: %s DATABASE ?OPTIONS? ?SCRIPT?\n", zTail);
   exit(1);
@@ -1338,6 +1345,7 @@ int SQLITE_CDECL main(int argc, char **argv){
 #endif
     runSql("PRAGMA journal_mode=%Q;", zJMode);
   }
+  if( !g.bSync ) trySql("PRAGMA synchronous=OFF");
   sqlite3_enable_load_extension(g.db, 1);
   sqlite3_busy_handler(g.db, busyHandler, 0);
   sqlite3_create_function(g.db, "vfsname", 0, SQLITE_UTF8, 0,
@@ -1346,7 +1354,6 @@ int SQLITE_CDECL main(int argc, char **argv){
                           evalFunc, 0, 0);
   g.iTimeout = DEFAULT_TIMEOUT;
   if( g.bSqlTrace ) sqlite3_trace(g.db, sqlTraceCallback, 0);
-  if( !g.bSync ) trySql("PRAGMA synchronous=OFF");
   if( iClient>0 ){
     if( n>0 ) unrecognizedArguments(argv[0], n, argv+2);
     if( g.iTrace ) logMessage("start-client");
diff --git a/src/main.c b/src/main.c
index d9ee77fab2..0e2f2bdc03 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1194,7 +1194,8 @@ void sqlite3RollbackAll(sqlite3 *db, int tripCode){
 ** Return a static string containing the name corresponding to the error code
 ** specified in the argument.
 */
-#if (defined(SQLITE_DEBUG) && SQLITE_OS_WIN) || defined(SQLITE_TEST)
+#if (defined(SQLITE_DEBUG) && SQLITE_OS_WIN) || \
+    (defined(SQLITE_TEST) || defined(SQLITE_FORCE_OS_TRACE))
 const char *sqlite3ErrName(int rc){
   const char *zName = 0;
   int i, origRc = rc;
diff --git a/src/os_common.h b/src/os_common.h
index f6c3e7ff89..0f5f779438 100644
--- a/src/os_common.h
+++ b/src/os_common.h
@@ -29,7 +29,8 @@
 # error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
 #endif
 
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+#if (defined(SQLITE_DEBUG) && SQLITE_OS_WIN) || \
+    (defined(SQLITE_TEST) || defined(SQLITE_FORCE_OS_TRACE))
 # ifndef SQLITE_DEBUG_OS_TRACE
 #   define SQLITE_DEBUG_OS_TRACE 0
 # endif
diff --git a/src/os_win.c b/src/os_win.c
index ef2f553f33..33a92b156e 100644
--- a/src/os_win.c
+++ b/src/os_win.c
@@ -25,6 +25,14 @@
 */
 #include "os_win.h"
 
+/*
+** Is the OSTRACE macro defined to actually do something?
+*/
+#if (defined(SQLITE_DEBUG) && SQLITE_OS_WIN) || \
+    (defined(SQLITE_TEST) || defined(SQLITE_FORCE_OS_TRACE))
+#  define SQLITE_WIN32_HAS_OS_TRACE
+#endif
+
 /*
 ** Compiling and using WAL mode requires several APIs that are only
 ** available in Windows platforms based on the NT kernel.
@@ -2757,7 +2765,7 @@ static int winSync(sqlite3_file *id, int flags){
   BOOL rc;
 #endif
 #if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
-    (defined(SQLITE_TEST) && defined(SQLITE_DEBUG))
+    defined(SQLITE_WIN32_HAS_OS_TRACE)
   /*
   ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
   ** OSTRACE() macros.
@@ -3434,7 +3442,7 @@ struct winShmNode {
   int nRef;                  /* Number of winShm objects pointing to this */
   winShm *pFirst;            /* All winShm objects pointing to this */
   winShmNode *pNext;         /* Next in list of all winShmNode objects */
-#ifdef SQLITE_DEBUG
+#if defined(SQLITE_DEBUG) || defined(SQLITE_WIN32_HAS_OS_TRACE)
   u8 nextShmId;              /* Next available winShm.id value */
 #endif
 };
@@ -3465,7 +3473,7 @@ struct winShm {
   u8 hasMutex;               /* True if holding the winShmNode mutex */
   u16 sharedMask;            /* Mask of shared locks held */
   u16 exclMask;              /* Mask of exclusive locks held */
-#ifdef SQLITE_DEBUG
+#if defined(SQLITE_DEBUG) || defined(SQLITE_WIN32_HAS_OS_TRACE)
   u8 id;                     /* Id of this connection with its winShmNode */
 #endif
 };
@@ -3656,7 +3664,7 @@ static int winOpenSharedMemory(winFile *pDbFd){
 
   /* Make the new connection a child of the winShmNode */
   p->pShmNode = pShmNode;
-#ifdef SQLITE_DEBUG
+#if defined(SQLITE_DEBUG) || defined(SQLITE_WIN32_HAS_OS_TRACE)
   p->id = pShmNode->nextShmId++;
 #endif
   pShmNode->nRef++;
diff --git a/src/printf.c b/src/printf.c
index 81efa057fc..b559e9dfc3 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -1045,7 +1045,8 @@ void sqlite3_log(int iErrCode, const char *zFormat, ...){
   }
 }
 
-#if defined(SQLITE_DEBUG)
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST) || \
+    defined(SQLITE_FORCE_OS_TRACE)
 /*
 ** A version of printf() that understands %lld.  Used for debugging.
 ** The printf() built into some versions of windows does not understand %lld
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 3841c91f14..45250bfd10 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -3491,7 +3491,8 @@ void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
 u8 sqlite3HexToInt(int h);
 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
 
-#if defined(SQLITE_TEST) 
+#if (defined(SQLITE_DEBUG) && SQLITE_OS_WIN) || \
+    (defined(SQLITE_TEST) || defined(SQLITE_FORCE_OS_TRACE))
 const char *sqlite3ErrName(int);
 #endif