To reproduce:
module load CPE/22.03
module load cray-mvapich2_nogpu_sve/2.3.6
git clone https://github.com/gchilders/msieve_nfsathome.git -b try_openmp
cd msieve_nfsathome
cc -O3 -h vector3 -D_FILE_OFFSET_BITS=64 -DNDEBUG -D_LARGEFILE64_SOURCE -DVBITS=128  -I. -Iaprcl -Iinclude -Ignfs -Ignfs/poly -Ignfs/poly/stage1 -h omp -DHAVE_OMP -DHAVE_MPI -c -o common/lanczos/cpu/lanczos_matmul0.o common/lanczos/cpu/lanczos_matmul0.c

Output:
   Error message      ::  Optimization internal error
   Error detected     ::  File 'pdgcs/v_vcg_mem.c', line 2068
   Initiated from     ::  Line 2129 (v_main.c)
   Optimizer built    ::  2021-06-10 (production)
   Vector Translation ::
   Loop near line     ::  32

   File               ::  common/lanczos/cpu/lanczos_matmul0.c
   Function           ::  mul_packed
   at or near line    ::  34

   File path          ::  /lustre/home/jchilders/msieve/msieve_nfsathome/common/lanczos/cpu/lanczos_matmul0.c
   Compiler hash      ::  b41be4fd2f71d91624d9e1ca3b930c852051692f
   Target             ::  arm-nsp1

Creating internal compiler error backtrace (please wait):
Unable to launch gdb in batch mode.
gdb either does not exist or is already attached.
Trying alternative backtrace mechanism...

[0x00000000dd2423] linux_backtrace :?
[0x00000000dd3293] pdgcs_internal_error(char const*, char const*, int) :?
[0x00000000dd352f] opt_error_and_abort(char const*, int) :?
[0x00000000f04ec3] dup_vstruct_expr(EXP_INFO, EXP_INFO, TYPE) :?
[0x00000000f04a9f] dup_vstruct_expr(EXP_INFO, EXP_INFO, TYPE) :?
[0x00000000f04b7b] dup_vstruct_expr(EXP_INFO, EXP_INFO, TYPE) :?
[0x00000000f0a67f] vcg_convert_struct_asg(int, int) :?
[0x00000000ce03cb] vcg_translate_loop() :?
[0x0000000067aa8b] vector_translation() :?
[0x0000000055312f] pdgcs_main :?
[0x0000000052b763] PDGCS_do_proc :?
[0x00000000499993] cvrt_proc_to_pdg :?
[0x0000000049a617] m_cvrt_to_pdg :?
[0x000000004c5143] process_scp :?
[0x000000004c6827] m_start_ipa :?
[0x00000000411b7f] main :?
[0x00400000b30de3] ?? ??:0
[0x0000000045be3f] _start :?

Note:  This is a non-debug compiler.  Technical support should
       continue problem isolation using a compiler built for
       debugging.

CC-7991 craycc: INTERNAL mul_packed, File = common/lanczos/cpu/lanczos_matmul0.c, Line = 34
  INTERNAL COMPILER ERROR:  "Optimizer internal error" (pdgcs/v_vcg_mem.c, line 2068, version b41be4fd2f71d91624d9e1ca3b930c852051692f)
make: *** [Makefile_cray:336: common/lanczos/cpu/lanczos_matmul0.o] Error 1