debug logs for openblas git e01b3d4b546d8 built with make USE_THREAD=0 NO_LAPACK=1 DEBUG=1 which resulted in the barcelona target
the interesting parts are input 221 which loads the two element vector and a nan following it into xmm5 the nan is probably a remnant from the previous run 2: $xmm2.v4_float = {2, 1, -nan(0x7fffff), 2.06249976} which then spreads to the result during the hadds beginning in input 420 it also happens with only SSE2, only disabling sse completely fixes the issue
gdb.txt.gz
Description: GNU Zip compressed data