Is it really needed to build the static version of cryptsetup? I see it's built both dynamic and static for initrd setups, but building things static against glibc makes these things huge.

It makes crypsetup build fail, I haven't been able to get cryptsetup to build if I don't build libgcrypt with both static and shared libs.

Even though cryptsetup is set to shared libs in the configure when watching the build you will see it build the shared libs first then build for static libs.

Here is the log entry from the build showing the static build

if gcc -DHAVE_CONFIG_H -I. -I. -I.. -I.. -I../lib -DDATADIR=\""/usr/share"\" -DLOCALEDIR=\""/usr/share/locale"\" -DLIBDIR=\""/usr/lib"\" -DPREFIX=\""/usr"\" -DSYSCONFDIR=\""/usr/etc"\" -DVERSION=\""1.0.6"\" -D_GNU_SOURCE -march=i686 -mtune=generic -O2 -pipe -MT cryptsetup.o -MD -MP -MF ".deps/cryptsetup.Tpo" -c -o cryptsetup.o cryptsetup.c; \
then mv -f ".deps/cryptsetup.Tpo" ".deps/cryptsetup.Po"; else rm -f ".deps/cryptsetup.Tpo"; exit 1; fi
/bin/sh ../libtool --tag=CC --mode=link gcc -march=i686 -mtune=generic -O2 -pipe -o cryptsetup -all-static cryptsetup.o -lpopt ../lib/libcryptsetup.la
mkdir .libs

See the -all-static ?
This was from a build where I built the static libs from libgcrypt

Maybe there is another way but I haven't been successful otherwise.

From the cryptsetup PKGBUILD file:

cd $startdir/src/$pkgname-$pkgver
./configure --prefix=/usr --enable-static
make || return 1
# include a static cryptsetup binary for initrd setups
install -D -m755 src/cryptsetup $startdir/pkg/sbin/cryptsetup.static || return 1
# install hook
install -D -m644 $startdir/src/encrypt_hook $startdir/pkg/lib/initcpio/hooks/encrypt
install -D -m644 $startdir/src/encrypt_install $startdir/pkg/lib/initcpio/install/encrypt

This is the bad boy.
See the static in configure?
I don't know if the static build is required

We cannot build this against klibc, I tried once and failed. I'd be glad to have stripped down klibc versions of cryptsetup and lvm that only support cryptsetup luksOpen/create and lvm vgscan/vgchange commands, but that is much work.

Right now, a static build is the only solution.

At my job I implemented an automatic installer using initramfs. I had to switch to uclibc and busybox to get most commands available. lvm2 doesn't build with klibc, but it does build with uclibc. Wouldn't a copy of uclibc and linking these tools dynamic against it be more suitable than trying to patch everything to work with klibc? Linking these tools static against glibc and including them in the initramfs image makes them larger than when linking them to uclibc and including that as dynamic library.

I've been thinking about that myself. It would certainly be much easier to use uclibc instead of klibc and to compile the kinit stuff from klibc against uclibc.