LTO question

[Bingfeng Mei]

Hello,
I have been playing with LTO. I notice that LTO doesn't work when
object files are achived into static library files and the final
binary is linked against them, although these object files are compiled
with -flto and I can see all the lto related sections in .a files.
Is this what is described in LTO Wiki page? 

"As an added feature, LTO will take advantage of the plugin feature 
in gold. This allows the compiler to pick up object files that may 
have been stored in library archives. "

So do I have to use gold to solve this issue? 

Many thanks,
Bingfeng