Re: Problem for using __attribute__((section(".text")))

[Ian Lance Taylor <iant at google dot com>]

Heyu Zhu <zhu.heyu@gmail.com> writes:

> File boot.c is like below:
>
>           int val[] __attribute__ ((section(".text"))) = {1, 2, 3, 4, 5 ,6};
>           int getval(int i) {
>                return val[i];
>           }
>
> Then i compile it use gcc-4.2.4 and binutils2.20
>
>         arm-elf-gcc boot.c -c -o boot.o
>
> It gives a warning:
>
>    /tmp/ccIlHjum.s: Assembler message:
>    /tmp/ccIlHjum.s:4: Warning: ignoring changed section attributes for .text
>
> What's wrong?  What should i do to remove the warning?

You are putting a writable variable in .text, so gcc is trying to make
.text be writable.  That fails, because .text was already implicitly
declared as read-only.

When using __attribute__ ((section)) you should normally stick to your
own sections, rather than trying to use existing ones.

You will in any case get a similar effect if you write
    const int val[] = ...

Ian