Build on sparc64 fails with "undefined reference to `fdt_check_full'"

Trying to build QEMU on sparc64 fails with:

[4648/8435] c++  -o qemu-system-ppc64 qemu-system-ppc64.p/softmmu_main.c.o libcommon.fa.p/ui_vnc-auth-sasl.c.o libcommon.fa.p/migration_colo-failover.c.o libcommon.fa.p/hw_input_vhost-user-input.c.o libcommon.fa.p/replay_replay-random.c.o libcommon.fa.p/hw_9pfs_codir.c.o libcommon.fa.p/hw_display_edid-region.c.o libcommon.fa.p/hw_net_vhost_net.c.o libcommon.fa.p/hw_isa_i82378.c.o libcommon.fa.p/backends_rng-egd.c.o libcommon.fa.p/hw_usb_core.c.o libcommon.fa.p/hw_pci-bridge_i82801b11.c.o libcommon.fa.p/net_tap.c.o libcommon.fa.p/hw_ipack_ipack.c.o libcommon.fa.p/hw_scsi_mptconfig.c.o libcommon.fa.p/hw_usb_libhw.c.o libcommon.fa.p/hw_display_sm501.c.o libcommon.fa.p/hw_net_rocker_rocker_world.c.o libcommon.fa.p/fsdev_qemu-fsdev.c.o libcommon.fa.p/backends_tpm_tpm_util.c.o libcommon.fa.p/net_tap-linux.c.o libcommon.fa.p/hw_net_rocker_rocker_fp.c.o libcommon.fa.p/hw_usb_dev-uas.c.o libcommon.fa.p/hw_net_fsl_etsec_miim.c.o libcommon.fa.p/net_queue.c.o libcommon.fa.p/hw_isa_isa-superio.c.o libcommon.fa.p/migration_global_state.c.o libcommon.fa.p/backends_rng-random.c.o libcommon.fa.p/hw_ipmi_ipmi_bmc_extern.c.o libcommon.fa.p/migration_postcopy-ram.c.o libcommon.fa.p/hw_scsi_megasas.c.o libcommon.fa.p/hw_acpi_acpi-stub.c.o libcommon.fa.p/hw_nvram_mac_nvram.c.o libcommon.fa.p/hw_net_pcnet-pci.c.o libcommon.fa.p/cpus-common.c.o libcommon.fa.p/hw_core_qdev-properties-system.c.o libcommon.fa.p/migration_colo.c.o libcommon.fa.p/ui_spice-module.c.o libcommon.fa.p/hw_usb_hcd-ehci-pci.c.o libcommon.fa.p/migration_exec.c.o libcommon.fa.p/hw_input_adb-kbd.c.o libcommon.fa.p/hw_timer_xilinx_timer.c.o libcommon.fa.p/hw_cpu_core.c.o libcommon.fa.p/chardev_msmouse.c.o libcommon.fa.p/migration_socket.c.o libcommon.fa.p/hw_9pfs_9p-synth.c.o libcommon.fa.p/backends_dbus-vmstate.c.o libcommon.fa.p/net_colo-compare.c.o libcommon.fa.p/hw_misc_macio_cuda.c.o libcommon.fa.p/hw_audio_intel-hda.c.o libcommon.fa.p/audio_audio_legacy.c.o
(...)
libio.fa libchardev.fa -Wl,--no-whole-archive -Wl,--warn-common -Wl,-z,relro -Wl,-z,now -m64 -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wl,-z,relro -Wl,--as-needed -fstack-protector-strong libmigration.fa -Wl,--start-group libqemuutil.a contrib/libvhost-user/libvhost-user.a libqmp.fa libhwcore.fa libblockdev.fa libblock.fa libcrypto.fa libauthz.fa libqom.fa libio.fa libchardev.fa @block.syms @qemu.syms /usr/lib/gcc/sparc64-linux-gnu/10/../../../sparc64-linux-gnu/libfdt.so /usr/lib/sparc64-linux-gnu/libcapstone.so -lepoxy -lgbm /usr/lib/sparc64-linux-gnu/libpixman-1.so /usr/lib/sparc64-linux-gnu/libz.so /usr/lib/sparc64-linux-gnu/libslirp.so /usr/lib/sparc64-linux-gnu/libglib-2.0.so -lrdmacm -libverbs -libumad -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 /usr/lib/gcc/sparc64-linux-gnu/10/../../../sparc64-linux-gnu/libsasl2.so @block.syms -lusb-1.0 /lib/sparc64-linux-gnu/libudev.so /usr/lib/sparc64-linux-gnu/libpng16.so -lvdeplug /usr/lib/sparc64-linux-gnu/libjpeg.so -pthread -luring -lgnutls -lutil -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lm -Wl,--export-dynamic -lgmodule-2.0 -lglib-2.0 -laio -luring -lgnutls -lnettle -lstdc++ -Wl,--end-group
/usr/bin/ld: libqemu-ppc64-softmmu.fa.p/hw_ppc_spapr_hcall.c.o: in function `h_update_dt':
./b/qemu/../../hw/ppc/spapr_hcall.c:1966: undefined reference to `fdt_check_full'
collect2: error: ld returned 1 exit status

Full build log available at: https://buildd.debian.org/status/fetch.php?pkg=qemu&arch=sparc64&ver=1%3A5.2%2Bdfsg-1&stamp=1607502300&raw=0

Looking at the build log, it seems like your system libfdt is version 1.4.6.
However, that fdt_check_full function is only properly available with
version >= 1.5.1, if I get that right.

As a workaround, you could try to run the configure script with
--enable-fdt=git (or of course update your system version to 1.5.1 if
somehow possible).

Indeed, libfdt has been failing to build from source on sparc64 since version 1.4.7 due to the testsuite crashing with unaligned access:

> https://buildd.debian.org/status/fetch.php?pkg=device-tree-compiler&arch=sparc64&ver=1.6.0-1&stamp=1605385435&raw=0

libfdt-dev probably contains some fancy pointer arithmetic resulting in unaligned access which is not allowed but not recognized by gcc.

The issue has been fixed in the device-tree-compiler package here:

> https://git.kernel.org/pub/scm/utils/dtc/dtc.git/commit/?id=b28464a550c536296439b5785ed8852d1e15b35b

I have filed a Debian bug report asking to backport the patch:

> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=977031

Nevertheless, qemu should check for the presence of libfdt >= 1.5.1, so this is still a valid bug report.


This is an automated cleanup. This bug report has been moved to QEMU's
new bug tracker on gitlab.com and thus gets marked as 'expired' now.
Please continue with the discussion here:

 https://gitlab.com/qemu-project/qemu/-/issues/255