My environment is Systemtap-20070929 snapshot,elfutils-0.128 and kernel-2.6.23-rc8.

keyhack.stp in examples dir fails with below message
=============================
Running stap -p4 -g
/home/systemtap/tmp/stap_testing_200710010650/src/testsuite/../examples/small_demos/keyhack.stp
FAIL: keyhack.stp
Pass 4: compilation failed.  Try again with more '-v' (verbose) options.

With -vvv option,
=====================================================
_hit put_nsproxy exit_task_namespaces get_uts_ns put_uts_ns utsname init_utsname
function__dwarf_tvar_get_event_code_0
function__dwarf_tvar_set_event_code_1/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.c:155:35:
error: macro "store_register" passed 2 arguments, but takes just 1

/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.c: In function
'function__dwarf_tvar_set_event_code_1':
/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.c:155: error:
'store_register' undeclared (first use in this function)
/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.c:155: error: (Each
undeclared identifier is reported only once
/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.c:155: error: for each
function it appears in.)
 probe_1105 probe_1106 enter_begin_probe enter_end_probe enter_kprobe_probe
enter_kretprobe_probe systemtap_module_init systemtap_module_exit probe_start
probe_exit
Execution times (seconds)
 preprocessing         :   0.12 (29%) usr   0.06 (26%) sys   0.84 (61%) wall   
2001 kB (18%) ggc
 lexical analysis      :   0.12 (29%) usr   0.09 (39%) sys   0.23 (17%) wall   
   0 kB ( 0%) ggc
 parser                :   0.10 (24%) usr   0.06 (26%) sys   0.20 (14%) wall   
5539 kB (51%) ggc
 tree gimplify         :   0.04 (10%) usr   0.00 ( 0%) sys   0.07 ( 5%) wall   
1227 kB (11%) ggc
 symout                :   0.02 ( 5%) usr   0.02 ( 9%) sys   0.03 ( 2%) wall   
1270 kB (12%) ggc
 TOTAL                 :   0.41             0.23             1.38             
10872 kB
make[1]: *** [/tmp/stapn9nfvG/stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.o] Error 1
make: *** [_module_/tmp/stapn9nfvG] Error 2
make: Leaving directory `/home/srinivasa/systemtap/linux-2.6.23-rc8'
Pass 4: compiled C into "stap_6b2ff8d48e7cf8d0a5c0071652a8e8d8_776.ko" in
1040usr/440sys/4381real ms.
Pass 4: compilation failed.  Try again with more '-v' (verbose) options.
Running rm -rf /tmp/stapn9nfvG
[root@llm27lp1 obj]#
[root@llm27lp1 obj]# uname -a
Linux llm27lp1.in.ibm.com 2.6.23-rc8 #2 SMP Mon Oct 1 18:31:44 IST 2007 ppc64
ppc64 ppc64 GNU/Linux
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