* MPROTECT

On NetBSD, guile is marked NOT_MPROTECT_SAFE.  However, guile is built
and then used during the build, and that version hits the same
problem:

      GEN      guile-procedures.texi
    allocating JIT code buffer failed: Permission denied
    jit.c:5612: fatal: assertion failed
    [1]   Broken pipe             cat alist.doc array-handle.doc array-map.doc a... |
	  Abort trap (core dumped) GUILE_AUTO_COMPILE=0 ../meta/build-env guild s...

Reported to guile-devel@ on 20200827.

Probably needs a "paxctl +m guile" for the binary (in .libs via
libtool) after build and before use as a build tool.


* with CONFIGURE_ARGS+=       --disable-tmpnam

as per https://debbugs.gnu.org/cgi/bugreport.cgi?bug=29001

Perhaps fixed upstream

\todo Explain why we want to give this arg.  Just vague best
practices?

* Without threads support, doesn't build:

  CCLD     libguile-3.0.la
ld: .libs/libguile_3.0_la-posix.o: in function `scm_tmpnam':
/scratch/wip/guile30/work/guile-3.0.1/libguile/posix.c:1605: warning: warning: tmpnam() possibly used unsafely, use mkstemp() or mkdtemp()
  CCLD     guile
ld: ./.libs/libguile-3.0.so: warning: warning: tmpnam() possibly used unsafely, use mkstemp() or mkdtemp()
ld: ./.libs/libguile-3.0.so: undefined reference to `scm_i_pthread_key_create'

Reported upstream as http://debbugs.gnu.org/cgi/bugreport.cgi?bug=40075

(Probably fixed in 3.0.3, based on bug)

Perhaps make a no-threads option, but it is not clear why we care
about the non-threaded case.

