to_string is not always available, so don't use it.

	libcody/
	* buffer.cc (MessageBuffer::AppendInteger): Workaround
	to_string's non-ubiquity.

We explicitly need to inlude netinet.h, (despite what happened on my test systems)

	libcody/
	* netclient.cc: Add netinet.h.

While this doesn't fix 98324, it was an omission.  Cribbed code from
libcpp to build libcody as PIC.

	libcody/
	* configure.ac: Add --enable-host-shared.
	* Makefile.in: Add FLAGPIC.
	* configure: Regenerated.

This asm was a useful place for gdb to drop a breakpoint and make it
clear where you were when debugging.  I took a punt that 'surely every
arch has a nop instruction'. Well, no, some apparently have nops with
operands (what, do nothing harder? :)

	libcody/
	* fatal.cc (HCF): Remove nop breakpoint lander.

Rather than early-include sys/socket.h, let's allow the includer to
tell cody no networking.

	libcody/
	* cody.hh: Allow user to set CODY_NETWORKING.
	gcc/cp/
	* mapper-resolver.cc: Remove early include of
	sys/socket.h.  Specify no CODY_NETWORKING instead.
	* module.cc: Specify no CODY_NETWORKING.

> The -enable-checking configure code in libcody didn't play well with
> us.  This just uses libcpp's configurey for that piece.

This doesn't set is_release anywhere, which means when --enable-checking*
or --disable-checking isn't specified, it always treats it as
--enable-checking=yes, while the normal gcc behavior is treat only trunk
as --enable-checking=yes and treat release branches as
--enable-checking=release by default.

On the other side, nothing uses those ac_assert_checking and
ac_valgrind_checking variables, so it is a waste to compute those.

2020-12-16  Jakub Jelinek  <jakub@redhat.com>

	* configure.ac: Compute is_release.
	(NMS_ENABLE_CHECKING): Simplify but not computing ac_assert_checking
	and ac_valgrind_checking the code doesn't use.
	* configure: Regenerated.

Before CWG DR 1955 the controlling expression for an #elif must be
syntactically correct, meaning this won't compile with C++11 compilers
such as gcc 4.8:

The solution is to define __has_include(X) as 0 for compilers that don't
support it.

The second problem is that when <source_location> is found, it is used
without the std:: qualification.

libcody/ChangeLog:

	* internal.hh: Define fallback macros for __has_builtin and
	__has_include. Use __has_builtin for __builtin_FILE and
	__builtin_LINE. Define alias for std::source_location.

The -enable-checking configure code in libcody didn't play well with
us.  This just uses libcpp's configurey for that piece.

	libcody/
	* configure.ac: Use libcpp's enable-checking code.
	* configure: Rebuilt.

There were still some dash-killing uses of +=.  Fixed thusly.

	* config.m4: Replace V+="..." with V="$V..."
	* configure: Rebuilt.

libcody/ChangeLog:

	* buffer.cc (MessageBuffer::Lex): Remove unused variable.

Older GCCs don't have all the exciting options we have now.  let's just
turn them off.

	libcody/
	* Makefile.in: Disable some flags.

I missed some other places that used +=

	* config.m4: Avoid var+=...
	* configure: Rebuilt

Apparently 'var+=...' is not a dash thing.  Fixed thusly.

	* config.m4: Avoid non-dash idiom
	* configure: Rebuilt.

Add ChangeLog files, so that update_version_git can then fill those in.

In order to separate compiler from build system, C++ Modules, as
implemented in GCC introduces a communication channel between those
two entities.  This is implemented by libcody.  It is anticipated that
other implementations will also implement this protocol, or use
libcody to provide it.

	* Makefile.def: Add libcody.
	* configure.ac: Add libcody.
	* Makefile.in: Regenerated.
	* configure: Regenerated.
	gcc/
	* Makefile.in (CODYINC, CODYLIB, CODYLIB_H): New. Use them.
	libcody/
	* configure.ac: New.
	* CMakeLists.txt: New.
	* CODING.md: New.
	* CONTRIB.md: New.
	* LICENSE: New.
	* LICENSE.gcc: New.
	* Makefile.in: New.
	* Makesub.in: New.
	* README.md: New.
	* buffer.cc: New.
	* build-aux/config.guess: New.
	* build-aux/config.sub: New.
	* build-aux/install-sh: New.
	* client.cc: New.
	* cmake/libcody-config-ix.cmake
	* cody.hh: New.
	* config.h.in: New.
	* config.m4: New.
	* configure: New.
	* configure.ac: New.
	* dox.cfg.in: New.
	* fatal.cc: New.
	* gdbinit.in: New.
	* internal.hh: New.
	* netclient.cc: New.
	* netserver.cc: New.
	* packet.cc: New.
	* resolver.cc: New.
	* server.cc: New.
	* tests/01-serialize/connect.cc: New.
	* tests/01-serialize/decoder.cc: New.
	* tests/01-serialize/encoder.cc: New.
	* tests/02-comms/client-1.cc: New.
	* tests/02-comms/pivot-1.cc: New.
	* tests/02-comms/server-1.cc: New.
	* tests/Makesub.in: New.
	* tests/jouster: New.