Some of the initial errors have to do with the static declarations of logTable and expTable. Here is the output...

libtool: compile:  clang -Wall -g -O2 -DNDEBUG -DDEBUGVM=0 -msse2 -DCOGMTVM=0 -pthread -DLSB_FIRST=1 -m64 -Wno-missing-braces -Wno-unknown-pragmas -Wno-unused-value -Wno-unused-label -Wno-unused-function -Wno-unused-variable -DHAVE_CONFIG_H -I/home/rabbit/vm-dev/opensmalltalk-vm/build.linux64x64/squeak.cog.spur/build -I/home/rabbit/vm-dev/opensmalltalk-vm/build.linux64x64/squeak.cog.spur/build -I/home/rabbit/vm-dev/opensmalltalk-vm/platforms/unix/vm -I/home/rabbit/vm-dev/opensmalltalk-vm/platforms/Cross/vm -I/home/rabbit/vm-dev/opensmalltalk-vm/spur64src/vm -I/usr/local/include -m64 -Wno-missing-braces -Wno-unknown-pragmas -Wno-unused-value -Wno-unused-label -Wno-unused-function -Wno-unused-variable -c /home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c  -fPIC -DPIC -o .libs/RSErasurePlugin.o
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:44:15: error: static declaration of 'exp' follows non-static declaration
static usqInt exp(sqInt a);
              ^
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:95:17: note: previous declaration is here
__MATHCALL_VEC (exp,, (_Mdouble_ __x));
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:48:15: error: static declaration of 'log' follows non-static declaration
static usqInt log(sqInt a);
              ^
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:104:17: note: previous declaration is here
__MATHCALL_VEC (log,, (_Mdouble_ __x));
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:166:29: error: redefinition of 'multiplicationTable' as different kind of symbol
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:50:26: note: previous definition is here
static unsigned short ** multiplicationTable(void);
                         ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:166:66: error: expected '}'
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:166:63: note: to match this '{'
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:180:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:201:11: warning: implicit declaration of function 'signal' is invalid in C99 [-Wimplicit-function-declaration]
                        return signal(Exception, "Argument 'divisor' is 0");
                               ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:201:18: error: use of undeclared identifier 'Exception'
                        return signal(Exception, "Argument 'divisor' is 0");
                                      ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:221:1: error: static declaration of 'exp' follows non-static declaration
exp(sqInt a)
^
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:95:17: note: previous declaration is here
__MATHCALL_VEC (exp,, (_Mdouble_ __x));
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:241:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(base)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:270:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:299:1: error: static declaration of 'log' follows non-static declaration
log(sqInt a)
^
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:104:17: note: previous declaration is here
__MATHCALL_VEC (log,, (_Mdouble_ __x));
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:304:3: warning: implicit declaration of function 'signal' is invalid in C99 [-Wimplicit-function-declaration]
                signal(RSErasureIllegalArgumentError, "zero argument");
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:304:10: error: use of undeclared identifier 'RSErasureIllegalArgumentError'
                signal(RSErasureIllegalArgumentError, "zero argument");
                       ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:307:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:320:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(value)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:328:9: warning: incompatible pointer types returning 'unsigned short **(void)' from a function with result type 'unsigned short **' [-Wincompatible-pointer-types]
        return multiplicationTable;
               ^~~~~~~~~~~~~~~~~~~
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:341:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:374:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:380:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:418:24: warning: implicit declaration of function 'signal' is invalid in C99 [-Wimplicit-function-declaration]
                        result = ((usqInt) (signal(Exception, "Argument 'divisor' is 0")));
                                            ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:418:31: error: use of undeclared identifier 'Exception'
                        result = ((usqInt) (signal(Exception, "Argument 'divisor' is 0")));
                                                   ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:434:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:455:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:496:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:506:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:550:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:560:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:590:3: warning: implicit declaration of function 'signal' is invalid in C99 [-Wimplicit-function-declaration]
                signal(RSErasureIllegalArgumentError, "zero argument");
                ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:590:10: error: use of undeclared identifier 'RSErasureIllegalArgumentError'
                signal(RSErasureIllegalArgumentError, "zero argument");
                       ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:593:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:596:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:638:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:645:2: warning: implicit declaration of function 'popthenPushInteger' is invalid in C99 [-Wimplicit-function-declaration]
        popthenPushInteger(2, result);
        ^
/home/rabbit/vm-dev/opensmalltalk-vm/src/plugins/RSErasurePlugin/RSErasurePlugin.c:695:5: warning: implicit declaration of function 'twosComplement' is invalid in C99 [-Wimplicit-function-declaration]
                ? twosComplement(a)
                  ^
24 warnings and 10 errors generated.
make[1]: *** [Makefile:177: RSErasurePlugin.lo] Error 1
make: *** [Makefile:582: RSErasurePlugin.la] Error 2

--
---
Kindly,
Robert