Mariadb "Illegal Instruction"

After the openwrt update from Kernel 4.14.70 to higher, MariaDB has a problem with accessing the database. It's a nice picture building, with no errors. But after running on the router, the program starts normally, but when accessing the database, "illegal instruction" pops up. This error also does not allow you to create a new database. It is not guilty of the kernel, because if I return to 4.14.70, after the compilation and run I have the same error. It's just that the problem started to be extinguished until the sources of OpenWRT were just updated to kernal 4.14.71.
What could be the reason for this? Update MariaDB to 10.2.18 did not help.
My router is Linksys WRT3200ACM.