+- Compile with --enable-error-on-warning without failure. Requires a
+ number of fixes, including num2integral.i.c and on some platforms
+ gc_os_dep.c. Also SCM_FIXABLE etc. will produce unavoidable
+ warnings on some platforms with some vars as written now. i.e. on
+ alphas, SCM_FIXABLE(some_int) is always true. We need more
+ conditional compilation or similar.
+