Notes About Linker Script

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Some notes about how to write linker script.

Linker Script

Linker script is used to instruct the linker to generate the final objective file.

here is an example:

see this for whole example.

Code

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SECTIONS 
{
    . = 0x50;

    /* same as .data : AT(0x100) */
    /* LMA is same as VMA by default*/
    .data :
    {
        *.o(.data)
        BYTE(0xcc)
    }

    v1 = .;
    /* LMA is different from VMA */
    .sec2 : AT(0x70)
    {
        LONG(.)
        BYTE(0xcf)
        LONG(.)
        LONG(ABSOLUTE(.))
        LONG(v1)
        BYTE(0xcf)
        *.o(.sec2)
        BYTE(0xcc)
    }

    v2 = .;
    .text : AT(0x90)
    {   
        BYTE(0xcc) 
        sample.o(.text)
        BYTE(0xcc)
    }


    .text : AT(0x110)
    {
        sample2.o(.text)
        BYTE(0xcc)
    }
    
    .rodata :
    {
        . = ALIGN(16);
        BYTE(0xcf)
        . = . + 50;
        BYTE(0xcf)
    }
}

Note

VMA : virtual memory address
LMA : load memroy address

. = xxx sets VMA
AT(xxx) sets LMA

Done.