message: build: Add -Werror=mismatched-tags
diff: @@ -425,6 +425,7 @@ if test "x$enable_werror" = "xyes"; then
  AX_CHECK_COMPILE_FLAG([-Werror=suggest-override],[ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Werror=suggest-override"],,[[$CXXFLAG_WERROR]],
  [AC_LANG_SOURCE([[struct A { virtual void f(); }; struct B : A { void f() final; };]])])
  AX_CHECK_COMPILE_FLAG([-Werror=unreachable-code-loop-increment],[ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Werror=unreachable-code-loop-increment"],,[[$CXXFLAG_WERROR]])
  + AX_CHECK_COMPILE_FLAG([-Werror=mismatched-tags], [ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Werror=mismatched-tags"], [], [$CXXFLAG_WERROR])
  fi
  if test "x$CXXFLAGS_overridden" = "xno"; then
  