gnat3.07 on AIX4.1.4: link problems

gnat3.07 on AIX4.1.4: link problems

[Meskovic Zlatko]

Hi all,

I have a little problem with linking ada on my PowerPC.

I ported (or should i say, i rewrote some packages) gnat3.07 to
PowerPC running AIX4.1.4 so that it uses pthreads for tasking.

Tasking is now running very well, i didn't discover any error until now.
But for building a program i have to run following script:

  gcc -c x.adb
  gnatbind x.ali
  gnatlink -gnatlink /bin/ld -o x x.ali \
    -L/usr/local/lib/gcc-lib/powerpc-ibm-aix4.1.4.0/2.7.2.1/ \
    -L/usr/lib/threads \
    -lgcc -lgnat /lib/crt0_r.o -lc_r -lc
                      ~~~~~~~~   ~~~

This i a little bit complicated and i would prefer to use gnatmake.

But when i use the normal 'gnatmake x.adb'
the program aborts with an exception
  raised STORAGE_ERROR
because gnatlink used only '/lib/crt0.o -lc' for linking.

When i run 'gnatmake x.adb -largs /lib/crt0_r.o -lc_r'
then i get the link warning
  ld: 0711-224 WARNING: Duplicate symbol: __start
  ld: 0711-224 WARNING: Duplicate symbol: .__start
  ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more information.

the -bnoquiet option says:
        The following duplicates were found:
 Symbol                    Source-File(Object) OR Import-File{Shared-object}
 ------------------------- -------------------------------------------------
 __start                   crt0main.s(/lib/crt0.o)
    ** Duplicate **        crt0main.s(/lib/crt0_r.o)
ld: 0711-224 WARNING: Duplicate symbol: .__start
 .__start                  crt0main.s(/lib/crt0.o)
    ** Duplicate **        crt0main.s(/lib/crt0_r.o)

############

It looks like gnatlink allways takes /lib/crt0.o first.

Now to my question:

  How can i force gnatlink _not_ to use /lib/crt0.o but 
  to use /lib/crt0_r.o -lc_r instead ???


thanks i advance for any help

  zlatko


--
Zlatko B. Meskovic
Union Bank of Switzerland
Bahnhofstrasse 41
CH-8021 Zuerich

Email: zlatko.meskovic@ubs.com
Phone: +41 - 236 82 50
FAX:   +41 - 236 94 40

Re: gnat3.07 on AIX4.1.4: link problems

[Meskovic Zlatko]

Pascal Obry wrote:
> 
> ...
>
> 1) first solution
>

I did not try this

> 2) second solution (the best)
> 
> There is a specs file under /.../lib/gcc-lib/.../2.7.2/.
> 
> In this file you'll find a section *startfile: that say which startup file
> to link with. You must use a variable to switch between crt0 and crt0_r.
> The line after *startfile: should read like this :
> 
> %{mcrtr:crt0_r%O%s} %{!mcrtr:crt0%O%s}
> 
> This mean that if crtr is defined then use crtO_r.o else use crt0.o
> 
> Now you must call gnatmake like this :
> 
> > gnatmake hello -largs -mcrtr
> 

I tried this one, and it works.

Where is a description of this specs file ?


thank you pascal

  zlatko

--
Zlatko B. Meskovic
Union Bank of Switzerland
Bahnhofstrasse 41
CH-8021 Zuerich

Email: zlatko.meskovic@ubs.com
Phone: +41 - 236 82 50
FAX:   +41 - 236 94 40

Re: gnat3.07 on AIX4.1.4: link problems

[Stephen Leake]

Pascal Obry wrote:
> =

> Meskovic Zlatko <zlatko.meskovic@ubs.com> a =E9crit dans l'article
> <32B502FC.41C6@ubs.com>...
> >
> > Where is a description of this specs file ?
> >
> =

> Have a look at the page from CYGNUS :
> http://www.cygnus.com/library/technical.html
> =


That's just the gcc info manual; it does not have a good description of
the specs file. The full documentation is in the gcc source, in the file
gcc.c; search for "specs". It's actually quite readable - at least, I
figured it out :).

-- =

- Stephe

Re: gnat3.07 on AIX4.1.4: link problems

[Ken Thomas]

[-- Attachment #1: Type: text/plain, Size: 752 bytes --]

Meskovic Zlatko wrote:
> 
> Hi all,
> 
> I have a little problem with linking ada on my PowerPC.
> 
It is good news that tasking is working on this version as I am
developing code for the parallel IBM SP2. One aspect of this is an Ada95
binding to MPI in which alternative startup code (crt0.o) is used.
After some experimentation the attached makefile was produced.
The "trick" is to use the option -nostartfiles as a parameter to
gnatlink. The MPI-Ada code is called from an enclosing C program.

Hope this helps.

Ken


-- 
Dr K.S. Thomas
Department of Electronics and Computer Science
University of Southampton
Highfield
Southampton SO17 1BJ
United Kingdom

Telephone : (+44) 01703 593029
Fax :       (+44) 01703 593903

email: kst@ecs.soton.ac.uk

[-- Attachment #2: Makefile --]
[-- Type: text/plain, Size: 797 bytes --]

MPI_LINK  = -nostartfiles -L/usr/lpp/ppe.poe/lib -L/usr/lpp/ppe.poe/lib/ip -lmpi -lvtd -lppe -lc
GNAT = -L/home/kst/SP2/GNAT.3.05/lib/gcc-lib/rs6000-ibm-aix3.2/2.7.2 -lgnat

EXTRA_LINK = /usr/lpp/ppe.poe/lib/crt0.o

wrapper1.o:	wrapper1.c
	mpcc -c -I/usr/lpp/ppe.poe/include wrapper1.c

wrapper.o:	wrapper.c
	gcc -c -I/usr/lpp/ppe.poe/include wrapper.c

test1.ali:	test1.adb
	gnatmake -c test1

test1:	wrapper1.o test1.ali
	gnatbind -n test1.ali
	gnatlink $(MPI_LINK) $(EXTRA_LINK) test1.ali wrapper1.o
	rm test1.ali
	

test2.ali:	test2.adb
	gnatmake -c test2

test2:	wrapper.o test2.ali
	gnatbind -n test2.ali
	gnatlink $(MPI_LINK)  $(EXTRA_LINK) test2.ali  wrapper.o
	rm test2.ali 

one.o:	one.c
	gcc -c -I/usr/lpp/ppe.poe/include one.c

one:	one.o
	gcc -o one $(MPI_LINK) $(EXTRA_LINK) one.o