Seems to be an error in the Makefile(s) in that the "make test" can
 not compile some code for the correct architecture : 

The process seems to begin well and fine : 

alpha$ LD_LIBRARY_PATH=`pwd` /usr/local/bin/gmake test 2>&1 | tee ../python_3.8.1_SunOS5.10_sparc64vii+.003.test.log
LD_LIBRARY_PATH=/usr/local/build/python_3.8.1_SunOS5.10_sparc64vii+.003 ./python -E -S -m sysconfig --generate-posix-vars ;\
if test $? -ne 0 ; then \
        echo "generate-posix-vars failed" ; \
        rm -f ./pybuilddir.txt ; \
        exit 1 ; \
fi
/opt/developerstudio12.6/bin/cc -c -xcode=pic32   -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib -D_REENTRANT -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib    -I../Python-3.8.1/Include/internal -IObjects -IInclude -IPython -I. -I../Python-3.8.1/Include -I/usr/local/include -D_TS_ERRNO -D_POSIX_PTHREAD_SEMANTICS -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 -I/usr/local/include -D_TS_ERRNO -D_POSIX_PTHREAD_SEMANTICS -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 -xcode=pic32 -DPy_BUILD_CORE -o Modules/_math.o ../Python-3.8.1/Modules/_math.c
cc: Warning: multiple use of -Q option, previous one discarded.
LD_LIBRARY_PATH=/usr/local/build/python_3.8.1_SunOS5.10_sparc64vii+.003 CC='/opt/developerstudio12.6/bin/cc' LDSHARED='/opt/developerstudio12.6/bin/cc -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib -G -R/usr/local/lib -L/usr/local/lib -R/usr/local/lib -L/usr/local/lib  ' OPT=''         _TCLTK_INCLUDES='' _TCLTK_LIBS=''       ./python -E ../Python-3.8.1/setup.py  build
running build
running build_ext
building '_struct' extension
creating build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr
creating build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr/local
creating build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr/local/build
creating build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr/local/build/Python-3.8.1
creating build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr/local/build/Python-3.8.1/Modules
.
.
.
/opt/developerstudio12.6/bin/cc -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib -G -R/usr/local/lib -L/usr/local/lib -R/usr/local/lib -L/usr/local/lib -R/usr/local/lib -L/usr/local/lib -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib -I/usr/local/include -D_TS_ERRNO -D_POSIX_PTHREAD_SEMANTICS -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 build/temp.solaris-2.10-sun4u.64bit-3.8-pydebug/usr/local/build/Python-3.8.1/Modules/_uuidmodule.o -L. -L/usr/local/lib -R/usr/local/lib -luuid -o build/lib.solaris-2.10-sun4u.64bit-3.8-pydebug/_uuid.so
cc: Warning: multiple use of -Q option, previous one discarded.
*** WARNING: renaming "_curses" since importing it failed: ld.so.1: python: fatal: relocation error: file build/lib.solaris-2.10-sun4u.64bit-3.8-pydebug/_curses.so: symbol acs32map: referenced symbol not found
*** WARNING: renaming "_curses_panel" since importing it failed: No module named '_curses'
INFO: Could not locate ffi libs and/or headers

Python build finished successfully!
The necessary bits to build these optional modules were not found:
_gdbm                 ossaudiodev                              
To find the necessary bits, look in setup.py in detect_modules() for the module's name.


The following modules found by detect_modules() in setup.py, have been
built by the Makefile instead, as configured by the Setup files:
_abc                  atexit                pwd                
time                                                           


Failed to build these modules:
_ctypes                                                        


Following modules built successfully but were removed because they could not be imported:
_curses               _curses_panel                            

running build_scripts
creating build/scripts-3.8
copying and adjusting /usr/local/build/Python-3.8.1/Tools/scripts/pydoc3 -> build/scripts-3.8
copying and adjusting /usr/local/build/Python-3.8.1/Tools/scripts/idle3 -> build/scripts-3.8
copying and adjusting /usr/local/build/Python-3.8.1/Tools/scripts/2to3 -> build/scripts-3.8
changing mode of build/scripts-3.8/pydoc3 from 644 to 755
changing mode of build/scripts-3.8/idle3 from 644 to 755
changing mode of build/scripts-3.8/2to3 from 644 to 755
renaming build/scripts-3.8/pydoc3 to build/scripts-3.8/pydoc3.8
renaming build/scripts-3.8/idle3 to build/scripts-3.8/idle3.8
renaming build/scripts-3.8/2to3 to build/scripts-3.8/2to3-3.8
../Python-3.8.1/install-sh -c -m 644 ../Python-3.8.1/Tools/gdb/libpython.py python-gdb.py
/opt/developerstudio12.6/bin/cc -c   -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib -D_REENTRANT -std=iso9899:2011 -errfmt=error -erroff=%none -errshort=full -xstrconst -xildoff -m64 -xmemalign=8s -xnolibmil -xcode=pic32 -xregs=no%appl -xlibmieee -mc -g -xs -ftrap=%none -Qy -xbuiltin=%none -xdebugformat=dwarf -xunroll=1 -xarch=sparc -L/usr/local/lib -R/usr/local/lib    -I../Python-3.8.1/Include/internal -IObjects -IInclude -IPython -I. -I../Python-3.8.1/Include -I/usr/local/include -D_TS_ERRNO -D_POSIX_PTHREAD_SEMANTICS -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 -I/usr/local/include -D_TS_ERRNO -D_POSIX_PTHREAD_SEMANTICS -D_LARGEFILE64_SOURCE -D_XOPEN_SOURCE=600 -xcode=pic32 -DPy_BUILD_CORE -o Programs/_testembed.o ../Python-3.8.1/Programs/_testembed.c
cc: Warning: multiple use of -Q option, previous one discarded.
/opt/developerstudio12.6/bin/cc -R/usr/local/lib -L/usr/local/lib -R/usr/local/lib -L/usr/local/lib    -o Programs/_testembed Programs/_testembed.o -Wl,-R,/usr/local/lib -L. -lpython3.8d -lsocket -lnsl -lintl -lrt -ldl -lsendfile  -lm   -lm 
ld: fatal: file /opt/developerstudio12.6/lib/compilers/crti.o: wrong ELF class: ELFCLASS32
ld: fatal: file processing errors. No output written to Programs/_testembed
gmake: *** [Makefile:709: Programs/_testembed] Error 2
alpha$ 

Manual intervention required : 

alpha$ 
alpha$ $CC $CFLAGS -R/usr/local/lib -L/usr/local/lib -o Programs/_testembed \
> Programs/_testembed.o -Wl,-R,/usr/local/lib -L. -lpython3.8d \
> -lsocket -lnsl -lintl -lrt -ldl -lsendfile -lm
alpha$ 

Then one may continue and the tests begin to run.