Type Errors When Building Simulink Model In Accelerator Mode

I'm trying to build a Simulink model in accelerator mode. The make command aborts due to an error which I am unsure how to interpret. What might cause the model to generate a variable with unknown type in the header file, and how could I go about identifying the root cause?

The error message is below:

C:\Users\**user**\Documents\Github\my-project\Trunk\slprj\accel\Model_Name\mex>if "all" == "" ("C:\PROGRA~3\MATLAB\SUPPOR~1\R2023b\3P778C~1.INS\MINGW_~1.INS\bin\mingw32-make.exe"  -f Model_Name.mk all )  else ("C:\PROGRA~3\MATLAB\SUPPOR~1\R2023b\3P778C~1.INS\MINGW_~1.INS\bin\mingw32-make.exe"  -f Model_Name.mk all )  
"C:\PROGRA~3\MATLAB\SUPPOR~1\R2023b\3P778C~1.INS\MINGW_~1.INS\bin/gcc" -c -fwrapv -m64 -O0 -msse2 -DMATLAB_MEX_FILE -DMATLAB_DEFAULT_RELEASE=R2018a -DCLASSIC_INTERFACE=1 -DALLOCATIONFCN=0 -DONESTEPFCN=0 -DTERMFCN=1 -DMULTI_INSTANCE_CODE=0 -DINTEGER_CODE=0  -DTID01EQ=0 -DMODEL=GE_PP_Dyn_HIL -DNUMST=3 -DNCSTATES=0 -DHAVESTDIO -DMDL_REF_SIM_TGT=1  @Model_Name_comp.rsp -o "Model_Name_acc.obj" "C:/Users/**user**/Documents/Github/my_project/Trunk/slprj/accel/Model_Name/Model_Name_acc.c" 
In file included from C:/Users/**user**/Documents/Github/my_project/Trunk/slprj/accel/Model_Name/Model_Name_acc.c:1:
C:/Users/**user**/Documents/Github/my_project/Trunk/slprj/accel/Model_Name/Model_Name_acc.h:567:37: error: unknown type name 'struct_cVcxiIY63o731tAqsjnkH'
struct_5fgT4gUTVgYc3gHbc2FLEB P_0 ; struct_cVcxiIY63o731tAqsjnkH P_1 ;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
mingw32-make: *** [Model_Name.mk:404: Model_Name_acc.obj] Error 1