Improve error reporting in the Windows port when env size is too large.

w32/subproc/misc.c (arr2envblk): Compute and return the size of
the environment passed to child process.

w32/subproc/sub_proc.c (process_begin): If the call to
CreateProcess failed with EINVAL, and the required environment
size was larger than 32KB, assume it's a Windows XP limitation,
and display an error message to that effect.

w32/subproc/proc.h (arr2envblk): Update prototype.

Copyright-paperwork-exempt: yes
* output.c: Ensure space for final nul byte in fmtbuf.

Copyright-paperwork-exempt: yes
* configure.ac: Fixup for newer autoconf/automake
* Rename MAP_PATHSEP to MAP_DIRSEP.
[SV 42249] Propagate correct rule status results.

* remake.c (update_file, update_file_1, check_dep): Return an enum
  update_status value instead of an int, and keep the highest value we
  find as we walk the graph so that the ultimate status is correct.
* tests/scripts/options/dash-q: Add a test for updating prerequisites.
NMakefile.template ($(OUTDIR)/posixfcn.obj): Fix a typo.

Copyright-paperwork-exempt: yes.
[SV 41983] Support omitting the text argument to $(file ...)

Reported by Tim Murphy <tnmurphy@gmail.com>
* function.c (func_file): Only write TEXT if it is not NULL.
* NEWS, doc/make.texi: Document the new feature
* tests/scripts/functions/file: Verify that the no-text version of
  $(file ...) works and doesn't add a newline.
* maintMakefile, various: Improve constification of the codebase.
* various: Assume ISO C89-compliant free() implementation.
Update the regression test harness to support VMS.

* config_flags_pm.com, test_make.com: set up and run the regression
test environment on VMS.
* tests/run_make_tests.pl [VMS]: Use an alternate rmdir()
implementation on VMS.
(run_make_with_options) [VMS]: Provide VMS-specific quoting and shell
invocations.
(set_more_defaults) [VMS]: Set default values when running on VMS.
* tests/test_driver.pl (vms_get_process_logicals) [VMS]: Retrieve the
proper values from %ENV on VMS.
(resetENV) [VMS]: Use it.
(toplevel) [VMS]: Fix a bug with opendir() on some logical_devices.
(compare_output) [VMS]: Convert VMS test output to a "standard" format.
(_run_command) [VMS]: Handle signals and exit codes the VMS way.
(remove_directory_tree_inner) [VMS]: Unlink all versions of the file.
* output.c (pump_from_tmp): [SV 42378] Flush the output file regularly.

Copyright-paperwork-exempt: yes
* read.c (eval): [SV 41677] Correct test for TAB vs. 8 spaces.
* arscan.c [ANDROID]: Android has no ar.h but supports archives.

Copyright-paperwork-exempt: yes
Fix defalt_makefiles[] for MS-Windows.

* read.c (read_all_makefiles) [WINDOWS32]: Remove the redundant
"makefile" and add "makefile.mak".

Copyright-paperwork-exempt: yes
[SV 42695] Fix compilation error on MS-Windows.

* main.c [WINDOWS32]: Don't declare 'program' as 'const char *',
since it is modified in 'main'.
Fix compilation on MS-Windows.

* makeint.h [WINDOWS32]: Don't declare 'program' as 'const char *',
since it is modified in 'main'.
Fix regression with "makefile" not being found on MS-Windows.

* read.c (read_all_makefiles) [WINDOWS32]: Recognize "makefile",
all-lowercase, as a makefile.  Reported by Michael Waeber
<waeber@gmail.com>.
Change the order of "makefile" and "Makefile" to match the manual.
* configure.ac, maintMakefile, w32/Makefile.am: Fix autotools issues.

Reported by Paul Eggert <eggert@cs.ucla.edu>
Enhance/fix VMS build environment

* config.h-vms.template: make sure the CRTL version is known
* makefile.com: always compile/link the guile module, remove VAXCRTL
parameter, new LIST parameter
* makefile.vms: always compile/link the guile module, use more
complete dependencies
* prepare_vms.com: helper to create a VMS config file when building
from a snapshot of the repository