Re: [RFC PATCH v2 3/8] tools/nolibc: i386: Implement syscall with 6 arguments

Ammar Faizi
2022-03-22T13:56:51Z

On 3/22/22 8:54 PM, Ammar Faizi wrote:
>
> Willy, something goes wrong here...
>
> ammarfaizi2@integral2:~/work/linux.work/tools/include/nolibc$ taskset -c 0 gcc -ffreestanding -nostdlib -nostartfiles test.c -o test -lgcc
> /usr/bin/ld: /tmp/ccHiYiks.o: warning: relocation against `environ' in read-only section `.text'
> /usr/bin/ld: /tmp/ccHiYiks.o: in function `getenv':
> test.c:(.text+0x1f76): undefined reference to `environ'
> /usr/bin/ld: test.c:(.text+0x1fc3): undefined reference to `environ'
> /usr/bin/ld: test.c:(.text+0x1ffc): undefined reference to `environ'
> /usr/bin/ld: test.c:(.text+0x2021): undefined reference to `environ'
> /usr/bin/ld: test.c:(.text+0x2049): undefined reference to `environ'
> /usr/bin/ld: warning: creating DT_TEXTREL in a PIE
> collect2: error: ld returned 1 exit status
> ammarfaizi2@integral2:~/work/linux.work/tools/include/nolibc$
>
>
> I suspect it's caused by commit:
>
> commit c970abe796019b3d576fd154a54b94efb35c02b1
> Author: Willy Tarreau <w@1wt.eu>
> Date:   Mon Mar 21 18:33:08 2022 +0100
>
>     tools/nolibc/stdlib: add a simple getenv() implementation
>     This implementation relies on an extern definition of the environ
>     variable, that the caller must declare and initialize from envp.
>     Signed-off-by: Willy Tarreau <w@1wt.eu>
>     Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
>
> I will take a look deeper on this...

This bug only exists when compiling without optimization.

--
Ammar Faizi