[erlang-patches] Float endianness in 15B

Michael Sperber <>
Fri Mar 23 09:20:27 CET 2012

On certain ARM machines, there's a problem with float endianness, which
has been reported many times before.  Symptons:


The problem is *not* that the ARM is not using IEEE 754, as is inferred


The ARM uses IEEE 754, but the two 32-bit words in the FP
representation are swapped wrt. Erlang's assumptions.

The fix to the source code is very simple, but the associated autoconf
hackery is a bit more extensive.

Such a fix is here:

git fetch git://github.com/bjorng/otp.git double_middle_endian

(This is the first time I'm submitting a fix to Erlang, and I needed our
resident git ninja to help me set up, so I hope you'll forgive me if I
did something wrong - let me know.)


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