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Altera_Forum's avatar
Altera_Forum
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19 years ago

Hello world build error!

Hi all,

When build the hello_world.c, I encount a error, Is any one can help me out?

the hello_world.c as follows: 

#include <linux/init.h># include <linux/module.h># include <linux/kernel.h>
static int hello_init(void)
{
printk (KERN_ALERT "Hello, world!\n");
return 0;
}
static void hello_exit (void)
{
printk (KERN_ALERT "Goodbye, cruel world\n");
}
module_init (hello_init);
module_exit (hello_exit);
MODULE_LICENSE("Dual BSD/GPL");

and the problem as follows: 

$ nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000"
In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/sched.h:16,
                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:9,
                 from linux-2.6.x/drivers/misc/hello.c:6:
/opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/signal.h:2:2: warning:# warning "You should include <signal.h>. This time I will do it for you."
In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/sched.h:79,
                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:9,
                 from linux-2.6.x/drivers/misc/hello.c:6:
/opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/resource.h:2:2: warning:# warning "You should include <sys/resource.h>. This time I will do it for you."
In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/asm/cache.h:25,
                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/cache.h:5,
                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:10,
                 from linux-2.6.x/drivers/misc/hello.c:6:
/opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/asm/nios.h:4:26: nios2_system.h: No such file or directory
In file included from linux-2.6.x/drivers/misc/hello.c:6:
/opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:41: error: field `attr&#39; has incomplete type
/opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:49: error: field `kobj&#39; has incomplete type
linux-2.6.x/drivers/misc/hello.c: In function `hello_init&#39;:
linux-2.6.x/drivers/misc/hello.c:14: error: `KERN_ALERT&#39; undeclared (first use in this function)
linux-2.6.x/drivers/misc/hello.c:14: error: (Each undeclared identifier is reported only once
linux-2.6.x/drivers/misc/hello.c:14: error: for each function it appears in.)
linux-2.6.x/drivers/misc/hello.c:14: error: syntax error before string constant
linux-2.6.x/drivers/misc/hello.c: In function `hello_exit&#39;:
linux-2.6.x/drivers/misc/hello.c:19: error: `KERN_ALERT&#39; undeclared (first use in this function)
linux-2.6.x/drivers/misc/hello.c:19: error: syntax error before string constant

It says the &#39;KERN_ALERT&#39; was not declared, but what try &#39;make&#39;, it has no problem.

Is that it need include other files in hello_world.c? How to build executable file for nios independent?

I hope anyone can help me out? ths!

8 Replies

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

    didn&#39;t you try 

    make ARCH=nios2nommu CROSS_COMPILE=nios2-linux-uclibc- -C ~/uClinux-dist/linux-2.6.x M=`pwd` modules

    which you will need to compile device drivers

    instead of 

    nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000"

    which suits for user programm.

    You will find detailed explanation in the kernel docs.

    hope this helps, but i&#39;m not a kernel crack

    maybe you take a look at the nioswiki for the module programming example.

    by the way let me ask you, what do you want to do?

    do you want to write a device driver or a user program.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    19 years ago

    --- Quote Start ---

    originally posted by helmchen@Feb 3 2007, 10:52 PM

    didn&#39;t you try 

    make arch=nios2nommu cross_compile=nios2-linux-uclibc- -c ~/uclinux-dist/linux-2.6.x m=`pwd` modules

    which you will need to compile device drivers

    instead of 

    nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000"

    which suits for user programm.

    you will find detailed explanation in the kernel docs.

    hope this helps, but i&#39;m not a kernel crack

    maybe you take a look at the nioswiki for the module programming example.

    by the way let me ask you, what do you want to do?

    do you want to write a device driver or a user program.

    <div align='right'><{post_snapback}> (index.php?act=findpost&pid=21184)</div>

    --- Quote End ---

    hi Helmchen,

    thank you very much for your reply, I&#39;m porting uCLinux on my own NiosII board, and start develope programme according to hippo&#39;s post:

    http://forum.niosforum.com/forum/index.php?showtopic=3174 (http://forum.niosforum.com/forum/index.php?showtopic=3174)

    when come to 11 tips, I have tied code he provided:

    ----------------- 

    nios2-linux-uclibc-gcc hello.c -o hello -elf2flt
cp hello ~/rootfs/bin

    Rebuild the kernel image for initramfs, boot nios2 uClinux, and run 

    hello

    -----------------

    Here the &#39;hello.c&#39; is a user programme, I mistake it to a device driver, and use 

    nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000"

    which is applied for user programme, so got the errors.

    Now I write a "hello world" user programme, and compiled successfully according the code.

    Thanks again!

    And I have a question:

    I have make a "hello_world" module which is a simple device driver, but I can only dynamic add it by "modprobe hello_world".

    Do you know how to add it with static method,namely add this module in when the kernel start?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    19 years ago

    <div class='quotetop'>QUOTE </div>

    --- Quote Start ---

    Do you know how to add it with static method,namely add this module in when the kernel start?[/b]

    --- Quote End ---

    Device Drivers -->

    Misc devices --->

    <*> example hello module

    Press <Space> several times to select the mode of the driver,

    <M> is module

    <*> is static linked to kernel

    < > unselect
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    18 years ago

    I want to know where i can find the hello module after the image is download into the DE2.Is it in the dir of /bin? but i can not find it.

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

    --- Quote Start ---

    originally posted by liuxiaoping@Mar 25 2007, 09:57 PM

    i want to know where i can find the hello module after the image is download into the de2.is it in the dir of /bin? but i can not find it.

    <div align='right'><{post_snapback}> (index.php?act=findpost&pid=22486)

    --- quote end ---

    --- Quote End ---

    All kernel modules will be in the /lib/modules/ <kernel version> tree.

    Don&#39;t mix up kernel modules with user apps.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    18 years ago

    To hippo:

    I am very sorry for my mistake,in fact,i did not find the module in the dir /lib,not /bin.In the dir of bin,i use the command ls,but there is only a file,i don&#39;t know why?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    18 years ago

    Make sure you have the hello.c in linux-2.6.x/drivers/misc, and you have updated Kconfig an Makefile in that dir.

    After "make" and "make linux images", in the uClinux-dist dir,

    please check if you have the hello.ko

    "tree linux-2.6.x/drivers/misc"

    "tree romfs/lib"

    Or you may check some other drivers or fs as modules, and find the modules of them.