Bison 3 breaks mariadb < 5.5.33. The latest available for mariadb is 5.5.56, which fails compilation on a libevent2 linking error.

I think someone on the build team had better take this one.

can you post some details here ?

if mariadb is assuming -levent works but failing because it needs -levent_core, then the fix is to get it to use pkg-config to locate libevent linkage.

there isn't really a "build team" to dump things onto anymore.  there is only the CrOS team, and we're all responsible.

cd /var/tmp/portage/dev-db/mariadb-5.5.56/work/mariadb-5.5.56_build/storage/tokudb/ft-index/ft && /usr/bin/x86_64-pc-linux-gnu-g++  -DHAVE_CONFIG_H -DTOKUDB_VERSION=tokudb-7.5.7 -DTOKUDB_VERSION_MAJOR=7 -DTOKUDB_VERSION_MINOR=5 -DTOKUDB_VERSION_PATCH=7 -D_DEFAULT_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 -D__LONG_LONG_SUPPORTED -D_$
CMakeFiles/async_queries.dir/async_queries.c.o: In function `next_event':
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:135: undefined reference to `event_set'
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:136: undefined reference to `event_add'
CMakeFiles/async_queries.dir/async_queries.c.o: In function `state_machine_handler':
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:301: undefined reference to `event_loopbreak'
CMakeFiles/async_queries.dir/async_queries.c.o: In function `main':
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:401: undefined reference to `event_init'
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:426: undefined reference to `event_dispatch'
/var/tmp/portage/dev-db/mariadb-5.5.56/work/mysql/tests/async_queries.c:432: undefined reference to `event_base_free'
collect2: error: ld returned 1 exit status

I see that mariadb is in both portage-stable and chromiumos-overlay. I was trying to upgrade the unpatched version in portage-stable. I'm going to open a new bug to upgrade mariadb as that may be a significant amount of work on its own.

looks like your log output has been snipped and doesn't show the entire link line

you should be able to patch mariadb in chromiumos-voerlay so that it uses the right pkg-config settings for libevent

Seems that this issue hasn't had attention in a while.

I've added a patch to update Bison to 3.0.4:
https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/1046375

I had also found a patch for MariaDB (from version 5.5.33) that refactors the deprecated directives so that it compiles with Bison 3.0.4 and 2.7.1:
https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/1045513

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/portage-stable/+/dea44874f4123c3b49c9010bf5f4c0c4c81a8710

commit dea44874f4123c3b49c9010bf5f4c0c4c81a8710
Author: Casey Bowman <casey.g.bowman@intel.com>
Date: Wed Jun 06 08:16:33 2018

bison: upgrade to 3.0.4-r1

BUG= chromium:710103 
TEST=emerge bison
TEST=bison --version shows 3.0.4

Change-Id: I111510696683845f1d4d21d808fe4fd1f142b8cb
Signed-off-by: Casey Bowman <casey.g.bowman@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/1046375
Commit-Ready: Casey G Bowman <casey.g.bowman@intel.com>
Tested-by: Prathyushi Nangia <prathyushi.nangia@intel.com>
Reviewed-by: Prathyushi Nangia <prathyushi.nangia@intel.com>
Reviewed-by: Yunlian Jiang <yunlian@chromium.org>

[add] https://crrev.com/dea44874f4123c3b49c9010bf5f4c0c4c81a8710/sys-devel/bison/bison-3.0.4-r1.ebuild
[modify] https://crrev.com/dea44874f4123c3b49c9010bf5f4c0c4c81a8710/sys-devel/bison/Manifest
[delete] https://crrev.com/49157b5bacdee09fb2359052dd31cf6c55c01d0b/sys-devel/bison/bison-2.7.1.ebuild