why do bit operations not work correctly

I'm at a complete loss! Why does my code not work as expected? I have the following code:

UINT64 tmpA = 0;
UINT64 tmpB = 0; 
UINT64 alarmed_lans = 0;
int foprtmsk[2]={0};
switch_fo_prtmsk_getptr(foprtmsk); 
tmpA = foprtmsk[1];                            
tmpB = foprtmsk[0];                            
gDbgLog("tmpA <%016llx>",tmpA);                
gDbgLog("tmpB <%016llx>",tmpB);                
gDbgLog("alarmed_lans <%016llx>",alarmed_lans);
alarmed_lans &= ((tmpA<<32) |tmpB);            
gDbgLog("alarmed_lans <%016llx>",alarmed_lans);

and the log produced looks like:

|0x1f604|7857[us]|fpga-alarm|fpga_faultlocalizer|tmpA <ffffffffeffeffff>
|0x1f6cb|7861[us]|fpga-alarm|fpga_faultlocalizer|tmpB <ffffffffffffffff>
|0x1f741|7863[us]|fpga-alarm|fpga_faultlocalizer|alarmed_lans <3003000000000000>
|0x1f7b8|7865[us]|fpga-alarm|fpga_faultlocalizer|alarmed_lans <3003000000000000>

Now, I'm wondering, why does the bitmask not get applied properly??? I'd expect to see

|0x1f7b8|7865[us]|fpga-alarm|fpga_faultlocalizer|alarmed_lans <2002000000000000>

What's going on here?

CPU: PPC85XXe500
compiler: diab
OS: VxWorks

Solution

alarmed_lans &= ((tmpA<<32) |tmpB);

alarmed_lans was never initialised. Using it results in undefined behaviour.
- tmpB is 0xfffff… (all 1s)
- OR that with anything and you get all 1s again.
- AND that with x and you get x

In theory, you should get the uninitialised value of alarmed_lans, but in practice, the compiler is allowed to do anything, including the invocation of nasal demons