MyStandaloneProgramDoesNotWork < DULG

%SECTION0{name=MyStandaloneProgramDoesNotWork}% My standalone program does not work


   Question:: I tried adding some new code to the =hellow_world.c=
     demo program. This works well as soon as I only add code to the
     existing hello_world() function, but as soon as I add some
     functions of my own, things go all haywire: the code of the
     hello_world() function does not get executed correctly, and my
     new function gets called with unexpected arguments.
     What's wrong?

   Answer:: You probably failed to notice that any code you add to
     the example program may shift the entry point address.
     You should check this using the =nm= program:
     <verbatim>
$ ${CROSS_COMPILE}nm -n examples/hello_world
0000000000040004 T testfunc
0000000000040058 T hello_world
000000000004016c t dummy
...
     </verbatim>
     As you can see, the entry point (function hello_world()) is no
     longer at 0x40004 as it was before and as it's documented.
     Instead, it is now at 0x40058. So you have to start
     your standalone program at this address, and everything should
     work well.

14.2.19. How can I create an uImage from a ELF file		1. Abstract		14.2.21. Linux hangs after uncompressing the kernel
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