I was able to successfully port both BOINC and seti_boinc into a workable S@H client, not that it matters much for the moment. However, I feel it might be useful to someone. I will share the binaries and an IPS installer file at a later date and will update this message accordingly. The changes aren't exactly revolutionary but it works.

These instructions, though brief, mirror my setup at https://kulowiec.com/seti/

-Nic

Obtain sources and patches:

wget -q https://github.com/BOINC/boinc/archive/client_release/7/7.14.zip
svn checkout https://setisvn.ssl.berkeley.edu/svn/seti_boinc
wget -q https://kulowiec.com/seti/boinc_7.14.2_patches.tar.gz
wget -q https://kulowiec.com/seti/seti_boinc_patches.tar.gz

## boinc ##

cd boinc-client_release-7-7.14
export MAKE=/usr/bin/gmake
export M4=/usr/bin/gm4
alias m4=/usr/bin/gm4
alias make=/usr/bin/gmake
./_autosetup 
./configure --disable-server --disable-manager --prefix=/usr/local
tar -xzf boinc_7.14.2_patches.tar.gz
patch configure configure.patch
patch lib/procinfo_unix.cpp lib/procinfo_unix.cpp.patch
patch client/mac_address.cpp client/mac_address.cpp.patch
gmake -j 96
gmake install

/* Continuing from boinc */
## seti_boinc ##

cd ../seti_boinc
tar -xzf seti_boinc_patches.tar.gz
patch client/seti.h client/seti.h.patch
patch client/vector/analyzeFuncs_vector.cpp client/vector/analyzeFuncs_vector.cpp.patch
patch Makefile.am Makefile.am.patch
./_autosetup
./configure --prefix=/usr/local --disable-server --disable-graphics BOINCDIR=../boinc-client_release-7-7.14
gmake -j 96
gmake install

PATCH FILES TEXT
## boinc ##
lib/procinfo_unix.cpp.patch

221c221
<         pm.insert(std::pair(p.id, p));
---
>         pm.insert(std::pair<int,PROCINFO>(p.id, p));

7.15.0
configure.patch

3743c3743
< REV=`echo '$Revision$' | awk "{print $2}"`
---
> REV=`echo '$Revision$' | awk '{print "$2"}'`

7.14.2
configure.patch

3830c3830
< REV=`echo '$Revision$' | awk "{print $2}"`
---
> REV=`echo '$Revision$' | awk '{print "$2"}'`

client/mac_address.cpp.patch

255c255
< #ifdef SIOCGIFHWADDR
---
> #ifdef defined(SIOCGIFHWADDR) &&  (!defined(__sun__))

## seti_boinc ##
Makefile.am.patch

13c13
<   CLIENT_SUBDIRS +=tools
---
> #  CLIENT_SUBDIRS +=tools

sah_config.h

781c781
< #define CUSTOM_STRING PACKAGE_STRING" "SVN_REV" "COMPILER_STRING
---
> #define CUSTOM_STRING PACKAGE_STRING " " SVN_REV " " COMPILER_STRING

client/seti.h.patch

56c56
< #define SINT8_FMT "%"PRId64
---
> #define SINT8_FMT "%" PRId64
58c58
< #define UINT8_FMT "%"PRIu64
---
> #define UINT8_FMT "%" PRIu64

client/vector/analyzeFuncs_vector.cpp.patch

102c102,104
< #define isnotnan(x) (!_isnan(x))
---
> #define isnotnan(x) (!isnand(x))
464,469d465
< #if (defined(__arm__) && defined(__VFP_FP__) && !defined(__SOFTFP__)) || defined(__arch64__)
<     v_pfTranspose2, BA_VFP, "v_pfTranspose2",      
<     v_pfTranspose4, BA_VFP, "v_pfTranspose4",      
<     v_pfTranspose8, BA_VFP, "v_pfTranspose8",      
<     v_vfpTranspose2, BA_VFP, "v_vfpTranspose2",
< #endif