Effect of the AT instruction

Erik Christiansen dvalin@internode.on.net
Wed Dec 20 11:45:00 GMT 2017


On 20.12.17 09:01, V S wrote:
> Hi !
> I'm trying to understand clearly the behavior of the AT instruction (see [1]).
> From my understanding, if I don't specify any AT or AT> to a region,
> its LMA will be equal to its VMA. However in practice, it seems that
> once I used AT once, the next LMA will be also affected by it, even if
> I don't recall it.
...
> Could anyone confirm that, or point me to the right documentation to
> understand what's really happening ?

With enough coffee, and a look at the list post cited below, maybe your
reference will do it:

...
> [1] https://sourceware.org/binutils/docs/ld/Output-Section-LMA.html

The third bullet point under the first heading, "3.6.8.2 Output Section
LMA", pretty much describes the behaviour, ISTM. As neither of your
output sections specified a VMA, and they're allocatable, the first
two bullet points don't apply.

This list post gives the timing of the change in behaviour, AIUI:
https://sourceware.org/ml/binutils/2008-03/msg00179.html

Erik



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