Re: cygwin64 - building 2.18.2 doc fails

[Masamichi HOSODA]

>> So, I use cygwin64 on 64 bit Windows.
>>
>> Has current 32 bit cygwin been fixed the such problem?
> 
> There was some improvement, specially as automatic rebase after
> install
> is now in place. But they are always possible.
> https://cygwin.com/faq.html#faq.using.fixing-fork-failures
> 
> 
> Anyway, I can assure you that I am familiar with the problem and
> it is NOT a fork issue.

I've reinstalled 32 bit cygwin to 64 bit Windows.
Then, lilypond-2.18.19's "make all"  is succeeded.

However, "make doc" is failed.
It seems "fork" issue.

I've tried "rebaseall".
However, the issue happened again.

```
GNU LilyPond 2.19.18
Processing `./snippet-map-1805178570.ly'
Parsing...
Processing `./91/lily-291ea81c.ly'
Parsing...
Renaming input to: 
`/home/trueroad/gcc/lilypond/lilypond-2.19.18/input/regression/unassociated-lyrics-alignment.ly'
Interpreting music...
Preprocessing graphical objects...
Interpreting music...
Preprocessing graphical objects...
Calculating line breaks... 
Drawing systems... 
Calculating line breaks... 
Drawing systems... 
Writing header field `texidoc' to `./91/lily-291ea81c.texidoc'...
Writing ./91/lily-291ea81c-1.signature
Writing ./91/lily-291ea81c-2.signature
Writing ./91/lily-291ea81c-3.signature
Writing ./91/lily-291ea81c-4.signature
Layout output to `./91/lily-291ea81c.eps'...
Converting to `./91/lily-291ea81c.pdf'...
Converting to PNG...
Layout output to `./91/lily-291ea81c-1.eps'...
Layout output to `./91/lily-291ea81c-2.eps'...
Layout output to `./91/lily-291ea81c-3.eps'...
Layout output to `./91/lily-291ea81c-4.eps'...
Converting to `./91/lily-291ea81c-1.pdf'...
      0 [main] lilypond 4944 fhandler_disk_file::fixup_mmap_after_fork: 
requested 0xFFFA0000 != 0x0 mem alloc base 0xFFEB0000, state 0x2000, size 
65536, Win32 error 487
  22995 [main] lilypond 4944 
C:\home\trueroad\gcc\lilypond\lilypond-2.19.18-build32\lily\out\lilypond.exe: 
*** fatal error in forked process - recreate_mmaps_after_fork_failed
  48026 [main] lilypond 4944 cygwin_exception::open_stackdumpfile: Dumping 
stack trace to lilypond.exe.stackdump
      1 [main] lilypond 5492 fork: child -1 - forked process 4944 died 
unexpectedly, retry 0, exit code 0x100, errno 11
failed (0): gs: Failed to fork (Resource temporarily unavailable)
```