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I want to specify the entry point to my ELF file using the linker script. I already defined some sections in my ELF, so want to set an entry point also withit. Can anyone tell me how to do it?

vimal prathap
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  • Related: C level: http://stackoverflow.com/questions/3097825/is-there-a-gcc-compiler-linker-option-to-change-the-name-of-main , assembly level: http://stackoverflow.com/questions/6563663/how-to-compile-assembly-whose-entry-point-is-not-main-with-gcc – Ciro Santilli OurBigBook.com Jul 13 '15 at 23:08

3 Answers3

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There's a special (GNU) linker script command that sets entry point to given symbol's address ENTRY(symbol). Refer to official documentation.

Werkov
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Looks like the command line argument -e entryName is the way to go about it. A man ld should give you a heads up as well.

CTS_AE
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First get the current linker script to a file with:

ld --verbose a.o | sed '/======/,/======/!d;//d' > myscript

Here we filtered the lines between =====, as mentioned at: How to select lines between two marker patterns which may occur multiple times with awk/sed

Then edit the ENTRY(_start) line to your desired symbol.

Finally use -T to select the custom script:

ld --verbose -T myscript a.o
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Ciro Santilli OurBigBook.com
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