Mine

make:

gcc   -DT38_SUPPORT  -pipe  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -g3  -Iinclude -I../include  -O6 -Wno-pointer-sign -march=k8          -m64 -fomit-frame-pointer  -include ../include/autoconfig.h -c -DSTANDALONE -o ast_expr2f.o ../ast_expr2f.c
yacc  ../ast_expr2.y 
mv -f y.tab.c ../ast_expr2.c
gcc   -DT38_SUPPORT  -pipe  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -g3  -Iinclude -I../include  -O6 -Wno-pointer-sign -march=k8          -m64 -fomit-frame-pointer  -include ../include/autoconfig.h -c -o ast_expr2.o ../ast_expr2.c
y.tab.c: In function 'yyparse':
y.tab.c:1379: warning: implicit declaration of function 'yylex'
y.tab.c:1770: warning: implicit declaration of function 'yyerror'
gcc  -DT38_SUPPORT  -pipe  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -g3  -Iinclude -I../include  -O6 -Wno-pointer-sign -march=k8          -m64 -fomit-frame-pointer  -g -o aelparse ../pbx/ael/aelflex.o ../pbx/ael/aelbison.o ael_main.o ../pbx/pbx_ael.o ../ast_expr2f.o ../ast_expr2.o
make[1]: Leaving directory `/devel/trunk/utils'

make install:

gcc  -DT38_SUPPORT  -pipe  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -g3  -Iinclude -I../include  -O6 -Wno-pointer-sign -march=k8          -m64 -fomit-frame-pointer  -include include/autoconfig.h   -c -o ast_expr2.o ast_expr2.c
y.tab.c: In function 'yyparse':
y.tab.c:1379: warning: implicit declaration of function 'yylex'
y.tab.c:1770: warning: implicit declaration of function 'yyerror'
build_tools/make_build_h > include/asterisk/build.h.tmp
if cmp -s include/asterisk/build.h.tmp include/asterisk/build.h ; then echo ; else \
                mv include/asterisk/build.h.tmp include/asterisk/build.h ; \
        fi
rm -f include/asterisk/build.h.tmp
gcc -c -o buildinfo.o  -DT38_SUPPORT  -pipe  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -g3  -Iinclude -I../include  -O6 -Wno-pointer-sign -march=k8          -m64 -fomit-frame-pointer  -include include/autoconfig.h buildinfo.c
gcc -g3  -o asterisk -Wl,-E  io.o sched.o logger.o frame.o loader.o config.o channel.o translate.o file.o pbx.o cli.o md5.o term.o ulaw.o alaw.o callerid.o fskmodem.o image.o app.o cdr.o tdd.o acl.o rtp.o udptl.o manager.o asterisk.o dsp.o chanvars.o indications.o autoservice.o db.o privacy.o astmm.o enum.o srv.o dns.o aescrypt.o aestab.o aeskey.o utils.o plc.o jitterbuf.o dnsmgr.o devicestate.o netsock.o slinfactory.o ast_expr2.o ast_expr2f.o cryptostub.o sha1.o http.o stdtime/localtime.o say.o buildinfo.o editline/libedit.a db1-ast/libdb1.a stdtime/libtime.a -ldl -lpthread -lncurses -lm -lresolv  
ast_expr2.o: In function `yyparse':/devel/trunk/y.tab.c:1770: undefined reference to `yyerror'
:/devel/trunk/y.tab.c:1379: undefined reference to `yylex'
:/devel/trunk/y.tab.c:1781: undefined reference to `yyerror'
:/devel/trunk/y.tab.c:1775: undefined reference to `yyerror'
:/devel/trunk/y.tab.c:1896: undefined reference to `yyerror'
ast_expr2f.o: In function `ast_expr':/devel/trunk/ast_expr2.fl:227: undefined reference to `ast_yyparse'
collect2: ld returned 1 exit status
make: *** [asterisk] Error 1