The Sun compiler points out that this code looks suspicious: if (decoded_length < 0) { return Qnil; XMALLOC_UNBIND (decoded, length * MAX_EMCHAR_LEN); } Also, here is a rewritten XMALLOC_OR_ALLOCA macro that avoids multiple evaluation of the `len' argument. #define XMALLOC_OR_ALLOCA(ptr, len, type) do { \ size_t XOA_len = (len); \ if (XOA_len > MAX_ALLOCA) \ { \ (ptr) = (type *)xmalloc (XOA_len * sizeof (type)); \ speccount = specpdl_depth (); \ record_unwind_protect (free_malloced_ptr, \ make_opaque_ptr ((void *)ptr)); \ } \ else \ (ptr) = alloca_array (type, XOA_len); \ } while (0) Martin