who knows about data in registers.....

[topscore]

who knows about mov command in gas assembler?
when there is a value in register say ,%r10= 0x3c00000000
and x=12
when you do the following command
movq x, %r10
i've got in %r10 register the value-0x3c0000000012

how can it be?
why x do not extend to register size 64 bits?

[Zugzwang]

Try to disassemble your program and check if it is really compiled the way it should be.