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Re: [ld, testsuite] XFAIL "pr20995-2", "Build" on arm*-*-eabi*

On Thu, Jan 26, 2017 at 05:16:01PM +0000, Jiong Wang wrote:
> disk size issue
> ===
> If we enable GNU relro support through defining COMMONPAGESIZE in emulparm
> then there will be observable impacts on disk size as LD will try to pad text
> section sometimes to save one memory page as the pad can avoid the duplicated
> mapping of the last page of text segment, this however will cause waste of up to
> COMMONPAGESIZE (0x1000 on arm at default) disk size.
> for example
> ===1.s===
> .text
> .fill 0x4, 1, 0
> .data
> .fill 0xffd, 1, 0
> as -o 1.o  1.s
> ld-new.original -o after.exe  1.o -e0
> ld-new.after -o before.exe  1.o -e0
> disk size before/after 37568/41660, a 4092 bytes increase.

I'll note that 32k or so of this is due to the combination of
TEXT_START_ADDR, EMBEDDED and MAXPAGESIZE.  So the concern about disk
size vs. relro would be better directed at fixing that, but please
don't ask me how to untangle emulparams/!

Alan Modra
Australia Development Lab, IBM

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