Eliding side-effect-free expression?

[Dave Nomura]

I have a tapscript that contains the following in the begin probe:
function init_qtrace ()
{
       // pull in all of the tapsets needed for generating qtrace format
       qtrace_cpu_init()
       qtrace_init()
}

qtrace_cpu_init() is defined in an i386/ subdirectory and earlier stap 
analysis reports:
   Searched 'qtrace/*.stp', found 2
   Searched 'qtrace/i386/*.stp', found 1

so I think it found the cpuinit.stp script in that defines 
qtrace_cpu_init() but I get the following message:
   Eliding side-effect-free expression identifier 'qtrace_cpu_init' at 
qtrace/qtrace.stp:1502:2

If I look at the generated C for 'function_init_qtrace' it appears to 
have removed the call to the tap function qtrace_cpu_init() which is 
defined as:
   function qtrace_cpu_init ()
   %{            printk("qtrace_cpu_init called\n");
       /* Initialize all structures, addrs and hardware specific to the 
CPU */
       if (!qtrace_cpu_init()) {
               printk("Error in initializing cpu data\n");
       }
   %}

So, my question is, why did STAP decide that this function 
qtrace_cpu_init() is side-effect free?

-- 
Dave Nomura
LTC Linux Power Toolchain