bug#65339: build failure on Android (Termux)

[Bruno Haible]

After working around bug#65319, the build of Emacs in the Termux app
on Android 11 fails like this:

$ make
...
cp -f temacs bootstrap-emacs
rm -f bootstrap-emacs.pdmp
./temacs --batch  -l loadup --temacs=pbootstrap \
        --bin-dest /usr/local/bin/ --eln-dest /usr/local/lib/emacs/30.0.50/
Loading loadup.el (source)...
Dump mode: pbootstrap
Using load-path (/data/data/com.termux/files/home/emacs/lisp 
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/data/data/com.termux/files/home/emacs/lisp/textmodes 
/data/data/com.termux/files/home/emacs/lisp/vc)
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Finding pointers to doc strings...
Finding pointers to doc strings...done
Dumping under the name bootstrap-emacs.pdmp
Dumping fingerprint: 
9d1f04d2a4bf5bdeb7c24c37906b24b3cbe2fa79fdbdcaed721520df25d33edb
Dump complete
Byte counts: header=100 hot=7809180 discardable=70896 cold=10881816
Reloc counts: hot=1082237 discardable=4753
fdsan: attempted to close file descriptor 2, expected to be unowned, actually 
owned by FILE* 0xb678438c
make[2]: *** [Makefile:1012: bootstrap-emacs.pdmp] Aborted
make[2]: *** Deleting file 'bootstrap-emacs.pdmp'
make[2]: Leaving directory '/data/data/com.termux/files/home/emacs/src'
make[1]: *** [Makefile:554: src] Error 2
make[1]: Leaving directory '/data/data/com.termux/files/home/emacs'
make[1]: Entering directory '/data/data/com.termux/files/home/emacs'
***
*** "make all" failed with exit status 2.

The line "fdsan: attempted to close file descriptor 2, expected to be unowned"
is apparently emitted by Android's "file descriptor sanitizer".

There's a discussion of this message here:
https://github.com/termux/termux-packages/issues/6592
and a workaround patch has been posted here:
https://github.com/termux/termux-packages/blob/master/packages/emacs/disable-fdsan.patch

With this workaround patch, the build gets much further: It produces a
working 'src/emacs' executable.

Would it be possible to
  - either change Emacs' FILE / dirfd handling so that it no longer produces
    this fdsan alert,
  - or include the workaround patch in Emacs upstream?

Bruno