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Altera_Forum's avatar
Altera_Forum
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20 years ago

implementing own _start function

Hi all,

I am trying to implement my own _start function. According to the hello_alt_main readme file any definition of _start in my directory will override the library definition.

If I built my project I get an error message saying that there are multiple definitions of _start and that it was first defined in crt0.S.

Obviously, my _start function does not just override the function in crt0.S

I define _start as global of type function

Any ideas?

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    No, I didn't, thanks for the hint!

    I am using the -nostartfiles flag now and provide my own crt0.S file. That just works fine and according to the linker, program size (code + initialized data) remains the same (196 bytes).

    I am using hello_led example for testing and changed the function name “alt_main” to “start_main”.

    There is just a minor difference in size of the elf file (3901 to 3473 bytes) which I do not know where it possibly could come from.

    --wolf
  • Altera_Forum's avatar
    Altera_Forum
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    20 years ago

    --- Quote Start ---

    originally posted by pfab@Nov 9 2005, 03:22 PM

    i am using hello_led example for testing and changed the function name “alt_main” to “start_main”.

    there is just a minor difference in size of the elf file (3901 to 3473 bytes) which i do not know where it possibly could come from.

    <div align='right'><{post_snapback}> (index.php?act=findpost&pid=10873)

    --- quote end ---

    --- Quote End ---

    Take a look at the objdump file to see if there are some functions more that are linked to the elf from the stdlib...

    Paolo