When I try to run the stock BOINC client 7.18. from the Ubuntu 22.04 LTS repository on an Intel Celeron J4105, it crashes due to an illegal instruction.

I traced it back to an AVX instruction in the function "RPC_CLIENT::RPC_CLIENT()" in "libboinc.so.7":

Program received signal SIGILL, Illegal instruction at:
0x00007ffff7f40b0a in RPC_CLIENT::RPC_CLIENT() from /lib/x86_64-linux-gnu/libboinc.so.7.

0x00007ffff7f40b0a: vxorpd %xmm0,%xmm0,%xmm0

Clearly, it's a case of the library having been built with the wrong CPU options, which should specify a generic x86-64 processor instead so that older processors may also be used.

The problem is that the client downloaded from this site also brings the same issue.

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