[LLVMdev] Why llvm values can't start with %1?

[Yuri]

After I manually modified .ll file deleting %0 I am getting this error 
from llvm-as:

lvm-as: my.ll:43:3: error: instruction expected to be numbered '%0'
  %1 = tail call noalias i8* @malloc(i32 8) nounwind ; <i8*> [#uses=1]
  ^

So now I have to also rename all other %<NUM> variables? Why llvm is so 
strict with naming? I think it should just accept whatever names are 
there as long as they make a valid .ll file.

Yuri