On Sun, 28 Sep 2003 11:58:54 +0200 (CEST), Akim Demaille wrote: > Could you make the test case smaller? Are you sure all the tests were > run with the modified m4? Okay, I narrowed down the "excess arguments to m4_pushdef" to the following tiny case: AC_INIT([crystal], [1], [someone]) AC_ARG_ENABLE([cpu-specific-optimizations], [AC_HELP_STRING([--enable-cpu-specific-optimizations=level], [foo, bar])], [], []) AC_OUTPUT It turns out that AC_HELP_STRING is the culprit. If I remove the comma from [foo, bar], then the error disappears. I suspect that the quoting in the new definition of AC_HELP_STRING in 2.57d is not working correctly when it calls the newly introduced AS_HELP_STRING. -- ES