Re: clang/llvm-tblgen --- ld: error: undefined symbol: setupterm

On Sun, Oct 10, 2021 at 02:52:58AM +0300, Konstantin Belousov wrote:
> On Sat, Oct 09, 2021 at 05:29:39PM -0600, Warner Losh wrote:
> > On Sat, Oct 9, 2021, 5:15 PM Konstantin Belousov <kostikbel@gmail.com>
> > wrote:
> > 
> > > On Sat, Oct 09, 2021 at 04:47:35PM -0600, Warner Losh wrote:
> > > > On Sat, Oct 9, 2021 at 11:09 AM Dimitry Andric <dim@freebsd.org> wrote:
> > > >
> > > > > On 9 Oct 2021, at 15:40, Warner Losh <imp@bsdimp.com> wrote:
> > > > > >
> > > > > > On Sat, Oct 9, 2021, 5:59 AM Dimitry Andric <dim@freebsd.org> wrote:
> > > > > > On 9 Oct 2021, at 13:37, Dimitry Andric <dim@FreeBSD.org> wrote:
> > > > > > >
> > > > > > > On 9 Oct 2021, at 09:46, FreeBSD User <freebsd@walstatt-de.de>
> > > wrote:
> > > > > > >>
> > > > > > >> On recent CURRENT (FreeBSD 14.0-CURRENT #2
> > > main-n249971-0525ece3554e:
> > > > > > >> Fri Oct  8 15:17:34 CEST 2021 amd64) building of an 13-STABLE
> > > based
> > > > > > >> appliance failed very early in the build process of the 13-STABLE
> > > > > > >> sources as shown below. 13-STABLE is most recent, since the
> > > sources
> > > > > are
> > > > > > >> fetched every time the build process is triggered.
> > > > > > > ...
> > > > > > >>
> > > > > /pool/home/ohartmann/Projects/router/router/apu2c4/src/tools/install.sh
> > > > > > >> -s -o root -g wheel -m 555   compile_et
> > > > > > >> /pool/home/ohartmann/Projects/router/router/apu2
> > > > > > >>
> > > > >
> > > c4/world/amd64/ALERICH_13-STABLE_amd64/pool/home/ohartmann/Projects/router/router/apu2c4/src/amd64.amd64/tmp/legacy/usr/bin/compile_et
> > > > > > >> --- _bootstrap-tools-usr.bin/clang/llvm-tblgen --- ld: error:
> > > > > undefined
> > > > > > >> symbol: setupterm
> > > > > > >>>>> referenced by Process.cpp
> > > > > > >>>>>
> > > > >  Process.o:(llvm::sys::Process::FileDescriptorHasColors(int))
> > > > > > >
> > > > > > > It is complaining about ncurses functions; it seems that even
> > > though
> > > > > the link step gets -lncursesw added, it still is not able to find the
> > > > > symbol:
> > > > > >
> > > > > > Okay, this is because recently on -CURRENT, libtinfow got split off
> > > from
> > > > > > libncursesw: https://cgit.freebsd.org/src/commit/?id=396851c20aebd
> > > > > >
> > > > > > This affects such cross-builds obviously, and manually adding
> > > -ltinfow
> > > > > > to the link command line makes it link correctly.
> > > > > >
> > > > > > However, the 396851c20aebd commit is probably not suitable for
> > > MFC'ing
> > > > > > to stable/13. Maybe we need to put some kind of kludge in
> > > > > > share/mk/src.libnames.mk for this, or in the top-level
> > > Makefile.inc1?
> > > > > >
> > > > > > Baptiste, any ideas? :)
> > > > > >
> > > > > > Add setupterm() to libegacy as a nop.
> > > > >
> > > > > That's not enough I think, it requires more ncurses functions than just
> > > > > setupterm. And it actually calls them and checks the return values too,
> > > > > IIRC. :)
> > > > >
> > > >
> > > > int setupterm(const char *t, int fd, int *errptr) { return OK; }
> > > > int tigetnum(const char *t) { return 0; }
> > > > TERMINAL *set_curterm(TERMINAL *t) { return NULL; }
> > > > int del_curterm(TERMINAL *t) { return OK; }
> > > >
> > > > should do the trick. I'll see just how crazy an idea this might be
> > > > since we're trying to get the first stage tool to work on a -current
> > > > host. the only thing that clang is really using is tigetnum to see
> > > > if the terminal has color. Returning 0 tells it no.
> > > >
> > > > Or we could contrive, during bootstrap, to ensure that
> > > > LLVM_ENABLE_TERMINFO is not defined. Nobody ever needs
> > > > color error messages. They are nice to have, sure, but are not
> > > > strictly needed if the alternative is monochrome error messages
> > > > while building the system. There's already an ifdef protecting it:
> > > >
> > > > /* Define if the setupterm() function is supported this platform. */
> > > > #if defined(__FreeBSD__)
> > > > /*
> > > >  * This is only needed for terminalHasColors(). When disabled LLVM falls
> > > > back
> > > >  * to checking a list of TERM prefixes which is sufficient for a
> > > bootstrap
> > > > tool.
> > > >  */
> > > > #define LLVM_ENABLE_TERMINFO 1
> > > > #endif
> > > >
> > > > It would be easy enough to add a && !defined(LLVM_BOOTSTRAP_BUILD)
> > > > or similar.
> > >
> > > I do not quite understand how would it help.
> > > You need to add this to HEAD sources back in time, not to the current
> > > sources.
> > >
> > 
> > Once merged, this would get stable building on current. But not older
> > versions of stable, it is true. It's worth doing for that reason alone
> > unless there's something clever we've not thought of yet with the current
> > host.
> 
> We can put somewhere a patch and add instructions how to use it to patch
> older HEADs and stable.  May be instructions and the reference to the patch
> file should go into UPDATING 20211004 entry.

It fails to link because the bootstrap tools are built statically if they were
linked dynamically that would solve the situation, because libncursesw.so is a
linkscript which does the right thing.
 
Stupid question, why are bootstrap tools statically linked in the first place?
If we remove -DNO_SHARED from the BARGS, it compiles perfectly fine.
  
Imho we should remove the static linking here, the other way would be to
provide a "flat" libncursesw.a for those cases on CURRENT. which I don't know how to
provide without breaking things even more.
   
Best regards,
Bapt