diff --git a/src/cf/osconf.m4 b/src/cf/osconf.m4
index 0c2faff338..4eff08ec64 100644
--- a/src/cf/osconf.m4
+++ b/src/cf/osconf.m4
@@ -258,8 +258,11 @@ case $AFS_SYSNAME in
 		PAM_CFLAGS="-Dlinux -DLINUX_PAM -fPIC"
 		SHLIB_LDFLAGS="-shared -Xlinker -x"
 		SHLIB_CFLAGS="-fPIC"
-		XCFLAGS="-D_LARGEFILE64_SOURCE -fPIC"
+		XCFLAGS="-D_LARGEFILE64_SOURCE -fPIC -m64"
 		SHLIB_LINKER="${MT_CC} -shared"
+		SHLIB_LINKER="${MT_CC} -shared -m64"
+		XLDFLAGS="-m64"
+		ASFLAGS="-a64"
 		;;
 
 	i386_linux*)
@@ -831,6 +834,7 @@ AC_SUBST(AIX32)
 AC_SUBST(AIX64)
 AC_SUBST(AR)
 AC_SUBST(AS)
+AC_SUBST(ASFLAGS)
 AC_SUBST(CP)
 AC_SUBST(DBG)
 AC_SUBST(FSINCLUDES)
diff --git a/src/config/Makefile.config.in b/src/config/Makefile.config.in
index 5a6ea7c6e7..22077a4c2b 100644
--- a/src/config/Makefile.config.in
+++ b/src/config/Makefile.config.in
@@ -32,6 +32,7 @@ viceetcdir=@viceetcdir@
 #
 AR = @AR@
 AS = @AS@
+ASFLAGS = @ASFLAGS@
 AFSD_LIBS = @AFSD_LIBS@
 AFSD_LDFLAGS = @AFSD_LDFLAGS@
 CC = @CC@
diff --git a/src/libafsrpc/Makefile.in b/src/libafsrpc/Makefile.in
index 7db4ab8828..54707caedd 100644
--- a/src/libafsrpc/Makefile.in
+++ b/src/libafsrpc/Makefile.in
@@ -389,7 +389,7 @@ syscall.o: ${SYS}/syscall.s
 	        ${CC} ${AFS_CFLAGS} -c syscall.c;; \
 	 *) \
 		$(PATH_CPP) ${SFLAGS} ${SYS}/syscall.s > syscall.ss; \
-		as -o syscall.o syscall.ss;		\
+		as $(ASFLAGS) -o syscall.o syscall.ss;		\
 		$(RM) syscall.ss;;				\
 	esac
 
diff --git a/src/libuafs/MakefileProto.LINUX.in b/src/libuafs/MakefileProto.LINUX.in
index fe14f9ae1a..9445119250 100644
--- a/src/libuafs/MakefileProto.LINUX.in
+++ b/src/libuafs/MakefileProto.LINUX.in
@@ -31,7 +31,7 @@ CFLAGS+= -I. -I.. -I${TOP_OBJDIR}/src/config ${FSINCLUDES} $(DEFINES) $(KOPTS) $
 OPTF=-O
 # WEBOPTS = -I../nsapi -DNETSCAPE_NSAPI -DNET_SSL -DXP_UNIX -DMCC_HTTPD
 
-TEST_CFLAGS=-pthread -D_REENTRANT -DAFS_PTHREAD_ENV -DAFS_LINUX22_ENV
+TEST_CFLAGS=-pthread -D_REENTRANT -DAFS_PTHREAD_ENV -DAFS_LINUX22_ENV $(XCFLAGS)
 TEST_LDFLAGS=
 TEST_LIBS=-lpthread
 
diff --git a/src/shlibafsrpc/Makefile.in b/src/shlibafsrpc/Makefile.in
index 3f7223c84a..eb6832ef4d 100644
--- a/src/shlibafsrpc/Makefile.in
+++ b/src/shlibafsrpc/Makefile.in
@@ -404,7 +404,7 @@ syscall.o: ${SYS}/syscall.s
                 ${CC} ${CFLAGS} -c syscall.c;; \
 	 *) \
 		$(PATH_CPP) ${SFLAGS} ${SYS}/syscall.s > syscall.ss; \
-		as -o syscall.o syscall.ss;		\
+		as $(ASFLAGS) -o syscall.o syscall.ss;		\
 		$(RM) syscall.ss;;				\
 	esac