[Clfs-support] Proper ABI selection for the ARMv4t platform

[Hector Oron]

Hi,

2011/4/5 Angel Ivan Castell Rovira <al004140 at gmail.com>:

> First, I am not sure if the ARM920T (v4t) is compatible with an EABI
> toolchain.

It is.

> Based on table 6.2 of the CLFS book, it seems version that ARM
> version 4 must be OABI, but based on section 6.3 (ABI variables), book says
> EABI is compatible with ARMv4t and newer cores. I selected OABI, but now I'm
> not sure if that was the best choice.

I would recommend revert to EABI. With a patch (not sure if it is at
CLFS) you can make v4 EABI build.

> If ARMv4t is EABI compatible, I will build my cross-toolchain again. But I
> have to select properly the value of the CLFS_ABI variable (based on the
> table 6.1, "aapcs" or "aapcs-linux"). Does some of you know the difference
> between both options?

aapcs defines enums to be a variable sized type, while with
aapcs-linux they are always ints (4 bytes)
From: http://wiki.debian.org/ArmEabiPort

> Also, If some of you have tested this issue... do you know the kind of
> errors expected when running a binary compiled with an EABI cross-toolchain
> on an OABI platform? Do you get "random illegal instructions" when running
> that binary or it does not work at all?

Please don't do that. http://wiki.debian.org/ArmEabiFixes might help.

Cheers,
-- 
 Héctor Orón  -.. . -... .. .- -.   -.. . ...- . .-.. --- .--. . .-.

"Our Sun unleashes tremendous flares expelling hot gas into the Solar
System, which one day will disconnect us."

-- Day DVB-T stop working nicely
Video flare: http://antwrp.gsfc.nasa.gov/apod/ap100510.html