gcc -Os -Wall -DFOSSIL_I18N=0 -L/mingw/lib -I/mingw/include  -I. -I./src -DSQLITE_OMIT_LOAD_EXTENSION=1 -DSQLITE_THREADSAFE=0 -DSQLITE_DEFAULT_FILE_FORMAT=4 -Dlocaltime=fossil_localtime -c ./src/sqlite3.c -o sqlite3.o
./src/sqlite3.c: In function `getLastErrorMsg':
./src/sqlite3.c:28450: warning: dereferencing type-punned pointer will break strict-aliasing rules

the warning is innocuous, but this patch resolves it. i'm pretty sure the code is correct, but i could use a code review. hopefully, i didn't make a noob mistake.

--- sqlite3.c
+++ sqlite3.c
@@ -28438,25 +28438,29 @@
   ** buffer, excluding the terminating null char.
   */
   DWORD error = GetLastError();
   DWORD dwLen = 0;
   char *zOut = 0;
+  union {
+    WCHAR** pzwc;
+    LPWSTR lpws;
+  } wu;

   if( isNT() ){
-    WCHAR *zTempWide = NULL;
+    *wu.pzwc = NULL;
     dwLen = FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                            NULL,
                            error,
                            0,
-                           (LPWSTR) &zTempWide,
+                           wu.lpws,
                            0,
                            0);
     if( dwLen > 0 ){
       /* allocate a buffer and convert to UTF8 */
-      zOut = unicodeToUtf8(zTempWide);
+      zOut = unicodeToUtf8(*wu.pzwc);
       /* free the system buffer allocated by FormatMessage */
-      LocalFree(zTempWide);
+      LocalFree(*wu.pzwc);
     }
 /* isNT() is 1 if SQLITE_OS_WINCE==1, so this else is never executed.
 ** Since the ASCII version of these Windows API do not exist for WINCE,
 ** it's important to not reference them for WINCE builds.
 */

dmitry added on 2011-09-08 19:18:24 UTC:
SQLite issue, indeed.