Comment # 1 on bug 1190340 from Guillaume GARDET

A local build shows a slightly different error:
[ 2568s]   GEN     modules.builtin
[ 2568s]   LD      .tmp_vmlinux.btf
[ 2598s]   BTF     .btf.vmlinux.bin.o
[ 2651s] [4956386] STRUCT cpu_context_save's field 'sp' offset=256 bit_size=0
type=4956171 Error emitting field
[ 2651s] Encountered error while encoding BTF.
[ 2651s]   LD      .tmp_vmlinux.kallsyms1
[ 2658s]   KSYMS   .tmp_vmlinux.kallsyms1.S
[ 2660s]   AS      .tmp_vmlinux.kallsyms1.S
[ 2663s]   LD      .tmp_vmlinux.kallsyms2
[ 2669s]   KSYMS   .tmp_vmlinux.kallsyms2.S
[ 2672s]   AS      .tmp_vmlinux.kallsyms2.S
[ 2674s]   LD      vmlinux
[ 2703s]   BTFIDS  vmlinux
[ 2703s] FAILED: load BTF from vmlinux: No such file or directory
[ 2703s] make[1]: ***
[/home/abuild/rpmbuild/BUILD/kernel-default-5.14.0/linux-5.14/Makefile:1200:
vmlinux] Error 255
[ 2703s] make[1]: *** Deleting file 'vmlinux'
[ 2704s] make: *** [../Makefile:220: __sub-make] Error 2