Re: [PATCH xfsprogs] configure: additionally get icu-uc from pkg-config

["Darrick J. Wong" <djwong@kernel.org>]

On Thu, Feb 13, 2025 at 10:39:29AM +0100, Alyssa Ross wrote:
> Alyssa Ross <hi@alyssa.is> writes:
> 
> > "Darrick J. Wong" <djwong@kernel.org> writes:
> >
> >> On Wed, Feb 12, 2025 at 09:16:49AM +0100, Alyssa Ross wrote:
> >>> This fixes the following build error with icu 76, also seen by
> >>> Fedora[1]:
> >>> 
> >>> 	/nix/store/9g4gsby96w4cx1i338kplaap0x37apdf-binutils-2.43.1/bin/ld: unicrash.o: undefined reference to symbol 'uiter_setString_76'
> >>> 	/nix/store/9g4gsby96w4cx1i338kplaap0x37apdf-binutils-2.43.1/bin/ld: /nix/store/jbnm36wq89c7iws6xx6xvv75h0drv48x-icu4c-76.1/lib/libicuuc.so.76: error adding symbols: DSO missing from command line
> >>> 	collect2: error: ld returned 1 exit status
> >>> 	make[2]: *** [../include/buildrules:65: xfs_scrub] Error 1
> >>> 	make[1]: *** [include/buildrules:35: scrub] Error 2
> >>> 
> >>> Link: https://src.fedoraproject.org/rpms/xfsprogs/c/624b0fdf7b2a31c1a34787b04e791eee47c97340 [1]
> >>> Signed-off-by: Alyssa Ross <hi@alyssa.is>
> >>
> >> Interesting that this pulls in libicuuc just fine without including
> >> icu-uc.pc, at least on Debian 12:
> >>
> >> $ grep LIBICU_LIBS build-x86_64/
> >> build-x86_64/include/builddefs:222:LIBICU_LIBS = -licui18n -licuuc -licudata
> >>
> >> Debian sid has the same icu 76 and (AFAICT) it still pulls in the
> >> dependency:
> >>
> >> Name: icu-i18n
> >> Requires: icu-uc
> >
> > I don't know too much about Debian, so I might be doing something wrong,
> > but when I looked in a fresh Debian Sid container I see a libicu-dev
> > package that's still on 72.1-6, a libicu76 package, but no libicu76
> > package.  I'm not sure there's currently a package that installs the
> > icu-i18n.pc from ICU 76?
> 
> Here I meant "no libicu75-dev package".

<nod> The development headers don't always have the version number
encoded in them; in this case it's libicu-dev that contains icu-i18n.pc
and icu-uc.pc.

> I suspect it's the following change:
> 
> https://github.com/unicode-org/icu/commit/199bc827021ffdb43b6579d68e5eecf54c7f6f56
> 
> I don't think there's anything special about Fedora here — I first saw
> this when the icu package was upgraded in Nixpkgs.

Hrmmm, this only seems to trigger if the libicu is configured with
--enable-shared.  Though, that seems to be the default...

*OH*.

libicu 76 exists only in Debian experimental, and there's not an
xfsprogs build for experimental.  Everything older than that (unstable
to bookworm) has libicu 72, which means that nobody in Debian land have
actually built xfsprogs against libicu 76.

Now that I've figured that out, can the commit message be changed to
reference the 199bc827021ffdb4 commit in upstream libicu (and provide
that link to the PR) as a motivation for changing the PKG_CHECK_MODULES
call?

"Upstream libicu changed its pkgconfig files[0] in version 76 to require
callers to call out to each .pc file they need for the libraries they
want to link against.  This apparently reduces overlinking, at a cost of
needing the world to fix themselves up.

"This patch fixes the following build error with icu 76, also seen by
Fedora[1]:

	/bin/ld: unicrash.o: undefined reference to symbol 'uiter_setString_76'
	/bin/ld: /lib/libicuuc.so.76: error adding symbols: DSO missing from command line
	collect2: error: ld returned 1 exit status
	make[2]: *** [../include/buildrules:65: xfs_scrub] Error 1
	make[1]: *** [include/buildrules:35: scrub] Error 2

"Link: https://github.com/unicode-org/icu/commit/199bc827021ffdb43b6579d68e5eecf54c7f6f56 [0]
"Link: https://src.fedoraproject.org/rpms/xfsprogs/c/624b0fdf7b2a31c1a34787b04e791eee47c97340 [1]"

With that fixed,
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D