Failure to build www/firefox

[Paul Goyette <paul%whooppee.com@localhost>]

Host system is amd64 running NetBSD 9..99.59, and pkgsrc is updated to
today.  I've rebuilt all dependencies from scratch into an initially 
sandbox, and now I'm getting a repeatable build error for firefox.

The first error message seems to be

	psutil/_psutil_common.c:9:10: fatal error: 'Python.h' file not found
	#include <Python.h>
	         ^~~~~~~~~~
	1 error generated.
	error: command 'gcc' failed with exit status 1

but it seems that this is not critical:

	Error processing command. Ignoring because optional. (optional:setup.py:third_party/python/psutil:build_ext:--inplace)
	Error processing command. Ignoring because optional. (optional:packages.txt:comm/build/virtualenv_packages.txt)
	Reexecuting in the virtualenv

However, we then get multiple errors similar to

	In file included from /tmp/pkgs/www/firefox/work.x86_64/firefox-76.0/js/src/frontend/Parser.cpp:20:
	In file included from /tmp/pkgs/www/firefox/work.x86_64/firefox-76.0/js/src/frontend/Parser.h:174:
	In file included from /tmp/pkgs/www/firefox/work.x86_64/build/dist/include/mozilla/Array.h:14:/tmp/pkgs/www/firefox/work.x86_64/build/dist/system_wrappers/ostream:3:15: fatal
	 error: 'ostream' file not found
	#include_next <ostream>
	              ^~~~~~~~~

There are multiple files mentioned in these errors, including "utility",
"type_traits", "cmath", and "new".

These errors all seem to be related to compiling "wrappers.cpp".

Any suggestions on how to fix?


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