* Re: Link start address [not found] <1186161144.23564.126.camel@shap.om-md.eros-os.com> @ 2007-08-03 17:30 ` Ramana Radhakrishnan 2007-08-03 17:44 ` Jonathan S. Shapiro 0 siblings, 1 reply; 3+ messages in thread From: Ramana Radhakrishnan @ 2007-08-03 17:30 UTC (permalink / raw) To: Jonathan S. Shapiro; +Cc: binutils Redirecting it there ... On 8/3/07, Jonathan S. Shapiro <shap@eros-os.com> wrote: > This is probably a question that should be directed to the binutils > list. > > We need to set the default link start address used by ld. Unfortunately > ld doesn't have a nice porting guide like GCC does. :-) Look at emulparams/*.sh and scriptempl/*.sc in the ld directory in binutils sources. You would need to set up TEXT_START_ADDRESS depending on your target to the correct address. Its a bunch of shell scripts that run to generate the default linker script and the corresponding start addresses. If you were however writing your own standalone linker script you'd do a . = <startaddress> in your linker script. > > Actually, we need to choose one of two possible start addresses based on > command line options to GCC, and I am wondering if this may make things > more complicated. You might want to have different linker options chosen - you could have different emul targets depending on the command line option you choose. You can control this using LINK_SPEC in the gcc driver . hope this helps cheers Ramana > > This is an ELF target. If we simply issue a --section-start for > the .init section from GCC, will the other sections get adjusted > accordingly under the generic linker script, or do we need to do > something more involved? > > If it's more involved, where to look? > > Bother. I used to know how to do this. :-) > > > shap > > -- Ramana Radhakrishnan ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: Link start address 2007-08-03 17:30 ` Link start address Ramana Radhakrishnan @ 2007-08-03 17:44 ` Jonathan S. Shapiro 2007-08-03 23:12 ` Ian Lance Taylor 0 siblings, 1 reply; 3+ messages in thread From: Jonathan S. Shapiro @ 2007-08-03 17:44 UTC (permalink / raw) To: Ramana Radhakrishnan; +Cc: binutils On Fri, 2007-08-03 at 23:00 +0530, Ramana Radhakrishnan wrote: > Redirecting it there ... > > On 8/3/07, Jonathan S. Shapiro <shap@eros-os.com> wrote: > > This is probably a question that should be directed to the binutils > > list. > > > > We need to set the default link start address used by ld. Unfortunately > > ld doesn't have a nice porting guide like GCC does. :-) > > Look at emulparams/*.sh and scriptempl/*.sc in the ld directory in > binutils sources. You would need to set up TEXT_START_ADDRESS > depending on your target to the correct address. Its a bunch of shell > scripts that run to generate the default linker script and the > corresponding start addresses. Isn't TEXT_START_ADDRESS the same as the address specified by the -Ttext option? If so, this is not sufficient. It causes the text section to move, but it does not cause the following sections (data, bss) to be adjusted. What I am looking for is a simple way to lower all of them. I will look at the places you mention. > > If you were however writing your own standalone linker script you'd do a > . = <startaddress> in your linker script. Yes. That I knew about. > > Actually, we need to choose one of two possible start addresses based on > > command line options to GCC, and I am wondering if this may make things > > more complicated. > > You might want to have different linker options chosen - you could > have different emul targets depending on the command line option you > choose. You can control this using LINK_SPEC in the gcc driver . > > hope this helps I was really hoping to avoid multiple emul targets, but I suppose that I should look at that. :-( Thanks again. shap ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: Link start address 2007-08-03 17:44 ` Jonathan S. Shapiro @ 2007-08-03 23:12 ` Ian Lance Taylor 0 siblings, 0 replies; 3+ messages in thread From: Ian Lance Taylor @ 2007-08-03 23:12 UTC (permalink / raw) To: Jonathan S. Shapiro; +Cc: Ramana Radhakrishnan, binutils "Jonathan S. Shapiro" <shap@eros-os.com> writes: > Isn't TEXT_START_ADDRESS the same as the address specified by the -Ttext > option? No, it isn't. TEXT_START_ADDRESS changes how the linker script lays out sections. -Ttext does not. Ian ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2007-08-03 23:12 UTC | newest] Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <1186161144.23564.126.camel@shap.om-md.eros-os.com> 2007-08-03 17:30 ` Link start address Ramana Radhakrishnan 2007-08-03 17:44 ` Jonathan S. Shapiro 2007-08-03 23:12 ` Ian Lance Taylor
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