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Re: [GOLD][PATCH] predefined segment symbol _begin


On Wed, 2010-02-10 at 17:16 -0800, Ian Lance Taylor wrote:
> Viktor Kutuzov <vkutuzov@accesssoftek.com> writes:
> 
> > I'm not sure. I have checked the ld scripts, but I didn't find anything
> > related with it. I looked for the _begin definition in the ld sources
> > and I got the same result. It looks strange for me, but anyway.
> > I seen that the _end and _etext symbols were resolved during the build,
> > but _begin wasn't and I added this description accordingly.
> 
> We're going to need to track this down.  I don't want to have gold
> start defining a symbol which the GNU linker does not.  Can you send
> the complete link line and error message that you get when using gold?
> Also include any linker script that may be used.  Thanks.

I have attached the text file with the complete link command line and
error message -- binutils-gold-glibc-link-cmd-line_and_error.txt.

You are right, the _begin symbol is coming from the linker script, but
the used ld script -- ld.so.lds -- is empty. I took one more look on the
build log and I found that the previous step should prepare an
appropriate ld script, which defines  _begin, but, really, doesn't do it
(attached binutils-gold-make-ld-script-cmd-line.txt contains the
complete cmd line). It happens because GOLD doesn't dump the linker
script on -verbose (GNU linker does), which is expected by the sed
script.

I have attached required linker script, which was generated with the gnu
linker for information (ld.so.lds-needed).

So, as result, a real problem is in another place and my patch is
incorrect. Please decline this patch. Sorry for the false alarm.

Thank you.
-Viktor.

Attachment: binutils-gold-glibc-link-cmd-line_and_error.txt
Description: Text document

Attachment: binutils-gold-make-ld-script-cmd-line.txt
Description: Text document

/* Script for --shared -z combreloc: shared library, combine & sort relocs */
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm",
	      "elf32-littlearm")
OUTPUT_ARCH(arm)
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SEARCH_DIR("=/usr/local/lib"); SEARCH_DIR("=/lib"); SEARCH_DIR("=/usr/lib");
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}



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