Library and linker errors

Library and linker errors

[Russ.Shaw]

Hi all,

I'm using gcc-2.95.5 configured as a cross-compiler for the
hitachi H8/300H cpu core. I'm using mandrake-7.0.

I found that h8300-hms-gcc gets its library files from:

/usr/local/h8300-hms/lib/libc.a
                         libg.a
                         libm.a
                         libiberty.a
and

/usr/local/lib/h8300-hms/libgcc.a (iirc)


However, i get lots of linker errors like:

/usr/local/h8300-hms/lib/libg.a(strtol.o)(.text+0xfa):strtol.c:
                                 undefined reference to '__umodsi3'
/usr/local/h8300-hms/lib/libg.a(strtol.o)(.text+0x10a):strtol.c:
                                 undefined reference to '__udivsi3'
/usr/local/h8300-hms/lib/libg.a(strtol.o)(.text+0x152):strtol.c:
                                 undefined reference to '__umulsi3'

I can't find where __umodsi3 etc are defined. In my makefile, i'm
linking ld using -lgcc -liberty -lg -lc -lm.


-- 
*******************************************
*   Russell Shaw, B.Eng, M.Eng(Research)  *
*      email: russell@webaxs.net          *
*      Australia                          *
*******************************************

gcc, crt0, and linker scripts...

[Russ.Shaw]

Hi all,

I'm using gcc-2.95.5 configured as a cross-compiler for the
hitachi H8/300H cpu core. I'm using mandrake-7.0.

I want to use h8300-hms-gcc to generate code for my own system.

However, what does gcc use for a linker script? I need to tell
gcc about my eprom memory map etc.

I could get gcc to use my own script using -Wl,T<myscript>, but
i'll still get linker errors because the output section names
need to be compatible with the supplied crt0 start-up file.

I can't use my own startup file, because the standard C libraries
refer to symbols such as _end in crt0.o.

So what is the 'normal' procedure for configuring a cross-gcc to
custom hardware? Also, in my install, i have these linker scripts:

/usr/local/h8300-hms/lib/ldscripts/h8300h.x
                                   h8300h.xbn
                                   h8300h.xn
                                   h8300h.xr
                                   h8300h.xu

I don't know if gcc knows about these or not.

-- 
*******************************************
*   Russell Shaw, B.Eng, M.Eng(Research)  *
*      email: russell@webaxs.net          *
*      Australia                          *
*******************************************

Re: Library and linker errors

[Alexandre Oliva]

On Aug  2, 2000, "Russ.Shaw" <russell@webaxs.net> wrote:

> I can't find where __umodsi3 etc are defined. In my makefile, i'm
> linking ld using -lgcc -liberty -lg -lc -lm.

You've got the order of libraries all wrong.  The order is important
because the linker only scans each library once.  Besides, I have the
impression that libg.a is just libc.a with debugging symbols.

Move -lm before -lc, then put -lgcc before *and* after -lc.

When in doubt, use gcc for linking, since it already does the right
thing regarding -lc and -lgcc.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me

Re: Library and linker errors

[Russ.Shaw]

Hi,

My last reply i sent last night bounced after 5 hours.

I got it all to compile and link now :)

The last error i was getting was that the _end symbol in some
C libraries remained undefined. I found that this was defined
in the supplied linker scripts:

/usr/local/h8300-hms/lib/ldscripts/h8300h.x
                                   h8300h.xbn
                                   h8300h.xn
                                   h8300h.xr
                                   h8300h.xu

So i added _end to my own script, and voila, no errors :)

I also found a gcc option for passing linker commands: -Wl,<linker opts>
which might be a way of telling it to use my own linker script.


Alexandre Oliva wrote:
> 
> On Aug  2, 2000, "Russ.Shaw" <russell@webaxs.net> wrote:
> 
> > I can't find where __umodsi3 etc are defined. In my makefile, i'm
> > linking ld using -lgcc -liberty -lg -lc -lm.
> 
> You've got the order of libraries all wrong.  The order is important
> because the linker only scans each library once.  Besides, I have the
> impression that libg.a is just libc.a with debugging symbols.
> 
> Move -lm before -lc, then put -lgcc before *and* after -lc.
> 
> When in doubt, use gcc for linking, since it already does the right
> thing regarding -lc and -lgcc.
> 
> --
> Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
> Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
> CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
> Free Software Evangelist    *Please* write to mailing lists, not to me

-- 
*******************************************
*   Russell Shaw, B.Eng, M.Eng(Research)  *
*      email: russell@webaxs.net          *
*      Australia                          *
*******************************************

Connecting stdin and stdout to serial port...

[Russ.Shaw]

Hi all,

I'm using gcc for the H8/3048, and am using the standard
C libraries.

To use scanf(), printf() etc, files need to be defined
for stdin and stdout. Somehow, these have to be connected
to the input and output of the rs232 serial port.

What's the usual way of doing this?

I currently have an array that gets filled by received
characters (interrupt driven), and an output array that
gets its contents emptied out the serial port when a
function triggers the tx interrupt. After the array
empties, the tx interrupt is disabled.

-- 
*******************************************
*   Russell Shaw, B.Eng, M.Eng(Research)  *
*      email: russell@webaxs.net          *
*      Australia                          *
*******************************************

Re: Connecting stdin and stdout to serial port...

[Alexandre Oliva]

On Aug  8, 2000, "Russ.Shaw" <russell@webaxs.net> wrote:

> I'm using gcc for the H8/3048, and am using the standard
> C libraries.

GCC has no standard C libraries.  In fact, your question has nothing
to do with GCC.  You should ask for help in C programming in
newsgroups or mailing-lists about C programming in general.

> To use scanf(), printf() etc, files need to be defined
> for stdin and stdout. Somehow, these have to be connected
> to the input and output of the rs232 serial port.

> What's the usual way of doing this?

freopen() or dup2()

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me