Re: Why is -O binary used in kbuild ?

[suneesh <suneesh@xxxxxxxxxxxxxx>]

matrix reloaded wrote:

> Hi, 
> 	I am going through the kbuild process and found that at some stage after 
> building vmlinux inside "/usr/src/linux/" somewhere kbuild uses objcopy to build 
> bzImage inside /usr/src/linux/arch/i386/boot/compressed :- 
>
> 1. objcopy -O binary -R .note -R .comment /usr/src/linux/vmlinux vmlinux.bin 
>
> Here, kbuild removes .note and .comment sections from vmlinux before making 
> vmlinux.bin. 
> Could anyone please explain why we are creating binary image of vmlinux here. 
> Basically, -O binary option creates a raw binary file which contains the memory 
> dumps of the contents of the input object files. What is the purpose behind this ? 
> objcopy with -O binary has been used in many places in kbuild process. Anyone 
> please help me... 
>
> Thanks in advance. 
> Sumit. 
>  
From objcopy man page,
     "objcopy can be used to generate a raw binary file by  using  an  
output
      target  of  binary (e.g., use -O binary).  When objcopy generates 
a raw
      binary file, it will essentially produce a memory dump of the  
contents
      of  the input object file.  All symbols and relocation 
information will
      be discarded.  The memory dump will start at the load  address  
of  the
      lowest section copied into the output file."


regards

Suneesh


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