configure: Build with -mcx16 on x86_64.

configure

@@ -10582,6 +10582,37 @@ fi
 $as_echo "$ac_cv_crosscflags__Wnonnull" >&6; }
 if test "x$ac_cv_crosscflags__Wnonnull" = xyes; then :
   EXTRACROSSCFLAGS="$EXTRACROSSCFLAGS -Wnonnull"
+fi
+                  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the cross-compiler supports -mcx16" >&5
+$as_echo_n "checking whether the cross-compiler supports -mcx16... " >&6; }
+if ${ac_cv_crosscflags__mcx16+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_wine_try_cflags_saved=$CFLAGS
+ac_wine_try_cflags_saved_cc=$CC
+ac_wine_try_cflags_saved_exeext=$ac_exeext
+CFLAGS="$CFLAGS $EXTRACROSSCFLAGS -nostartfiles -nodefaultlibs -mcx16"
+CC="$CROSSCC"
+ac_exeext=".exe"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+int __cdecl mainCRTStartup(void) { return 0; }
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_crosscflags__mcx16=yes
+else
+  ac_cv_crosscflags__mcx16=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+CFLAGS=$ac_wine_try_cflags_saved
+CC=$ac_wine_try_cflags_saved_cc
+ac_exeext=$ac_wine_try_cflags_saved_exeext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_crosscflags__mcx16" >&5
+$as_echo "$ac_cv_crosscflags__mcx16" >&6; }
+if test "x$ac_cv_crosscflags__mcx16" = xyes; then :
+  EXTRACROSSCFLAGS="$EXTRACROSSCFLAGS -mcx16"
 fi ;;
         esac
 

configure.ac

@@ -1096,7 +1096,8 @@ then
           *i[[3456789]]86*) WINE_TRY_CROSSCFLAGS([-fno-omit-frame-pointer]) ;;
           x86_64) WINE_TRY_CROSSCFLAGS([-Wno-format])
                   WINE_TRY_CROSSCFLAGS([-Wformat-overflow])
-                  WINE_TRY_CROSSCFLAGS([-Wnonnull]) ;;
+                  WINE_TRY_CROSSCFLAGS([-Wnonnull])
+                  WINE_TRY_CROSSCFLAGS([-mcx16]) ;;
         esac
 
         dnl Determine debug info format