Bug#45288: pb2 returns a lot of compilation warnings

Ensure that fdatasync is properly declared as on Mac OS X, the
function is available but there is no prototype. Also, port a
fix for a warning from the InnoDB plugin over to the builtin. 

configure.in:
  Check that fdatasync is declared.
mysys/my_sync.c:
  Use fdatasync only if it is declared.
storage/innobase/include/ut0dbg.h:
  Port over from the plugin a fix for a warning.

configure.in

@@ -2073,6 +2073,13 @@ MYSQL_TYPE_QSORT
 AC_FUNC_UTIME_NULL
 AC_FUNC_VPRINTF
 
+AC_CHECK_DECLS([fdatasync],,,
+[
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+])
+
 AC_CHECK_FUNCS(alarm bfill bmove bsearch bzero \
   chsize cuserid fchmod fcntl \
   fconvert fdatasync fesetround finite fpresetsticky fpsetmask fsync ftruncate \

mysys/my_sync.c

@@ -58,7 +58,7 @@ int my_sync(File fd, myf my_flags)
     /* Some file systems don't support F_FULLFSYNC and fail above: */
     DBUG_PRINT("info",("fcntl(F_FULLFSYNC) failed, falling back"));
 #endif
-#if defined(HAVE_FDATASYNC)
+#if defined(HAVE_FDATASYNC) && HAVE_DECL_FDATASYNC
     res= fdatasync(fd);
 #elif defined(HAVE_FSYNC)
     res= fsync(fd);

storage/innobase/include/ut0dbg.h

@@ -39,7 +39,7 @@ extern ibool	panic_shutdown;
 void ut_dbg_panic(void);
 # define UT_DBG_PANIC ut_dbg_panic()
 /* Stop threads in ut_a(). */
-# define UT_DBG_STOP	while (0)	/* We do not do this on NetWare */
+# define UT_DBG_STOP	do {} while (0)	/* We do not do this on NetWare */
 #else /* __NETWARE__ */
 # if defined(__WIN__) || defined(__INTEL_COMPILER)
 #  undef UT_DBG_USE_ABORT
@@ -71,7 +71,7 @@ ut_dbg_stop_thread(
 /* Abort the execution. */
 #  define UT_DBG_PANIC abort()
 /* Stop threads (null operation) */
-#  define UT_DBG_STOP while (0)
+#  define UT_DBG_STOP do {} while (0)
 # else /* UT_DBG_USE_ABORT */
 /* Abort the execution. */
 #  define UT_DBG_PANIC					\