When AC_PROG_CC detects GCC, Make.mk adds a bunch of flags to CFLAGS.
Works only for flags that any version of gcc in use accepts.
Instead, make configure add the flags that actually work to CFLAGS.
This will let us add flags that work only for some compilers.
The new autoconf macros are from autoconf-archive v2015.02.24.
Unfortunately, AX_APPEND_COMPILE_FLAGS doesn't work reliably for
-Wno-*: gcc complains about unknown -Wno-foo only when other
diagnostics are being produced. Test -Wfoo instead of -Wno-foo, and
rename to MY_APPEND_COMPILE_FLAGS.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Why upgrade? I'm not a lawyer, but here's my take on the differences
to version 2:
* Software patents: better protection against abuse of patents to
prevent users from exercising the rights under the GPL. I doubt
we'll get hit with a patent suit, but it's a good move just on
general principles.
* License compatibility: compatible with more free licenses, i.e. can
"steal" more free software for use in Empire. I don't expect to steal
much, but it's nice to have the option.
* Definition of "source code": modernization of some details for today's
networked world, to make it easier to distribute the software. Not
really relevant to us now, as we normally distribute full source code.
* Tivoization: this is about putting GPL-licensed software in hardware,
then make the hardware refuse to run modified software. "Neat" trick
to effectively deny its users their rights under the GPL. Abuse was
"pioneered" by TiVo (popular digital video recorders). GPLv3 forbids
it. Unlikely to become a problem for us.
* Internationalization: more careful wording, to harden the license
outside the US. The lawyers tell us it better be done that way.
* License violations: friendlier way to deal with license violations.
This has come out of past experience enforcing the GPL.
* Additional permissions: Probably not relevant to us.
Also include myself in the list of principal authors.
configure checked for library functions with LIBS instead of
LIBS_server, which could break detection of getaddrinfo() on systems
where LIB_SOCKET isn't empty.
GNUmakefile put @PTHREAD_LIBS@ only in LDLIBS, which breaks linking of
server and possibly client on systems where it is not empty.
Broken in commit 8b778634.
Make configure compute three sets of libraries: LIBS_client for the
client, LIBS_server for the server, and LIBS for the rest. This
replaces termlibs.
Unfortunately, LIBS doesn't work with Windows, because
src/lib/w32/posixio.c pulls in socket stuff. Temporary workaround:
use LIBS_server instead.
Checking Windows libraries with autoconf is cumbersome, because
linking often fails unless you include the header, and AC_SEARCH_LIBS
doesn't permit that.
Just detect the Windows API instead, with new MY_WINDOWS_API.
getpass() is traditional Unix, but has been withdrawn from POSIX. As
such, it may be missing. Check for that, and provide ersatz. It's
not a real replacement, because it doesn't do the special magic
getpass() is supposed to do: read from /dev/tty without echo.
This bypasses our existing getpass() for Windows. In contrast to the
portable getpass(), the Windows one tries to turn off echo, but that
doesn't work for me (MinGW & Wine). Remove it.
Detect .git instead of CVS. Use git-ls-files with git, else
$(srcdir)/sources.mk. info/findsubj.pl now gets the info files as
arguments rather than from sources.mk.
Remaking info subjects doesn't quite work, but it was broken similarly
before.
