Aha. Looks like the "target word size" is incorrect in the binary-dist version. 
Here's arm-apple-darwin10ghc --info (i.e., the binary-dist version)
http://lpaste.net/99489

and here's arm-apple-darwin10-ghc --info (from a working 'make install'ed version)
http://lpaste.net/99490

A bad settings file, I guess. I'll see if I can fix that...
Cheers
Luke


On Tue, Feb 4, 2014 at 8:59 PM, Luke Iannini <lukexipd@gmail.com> wrote:
OK, I've made a bit of progress here.

Again, I have very little understanding of the binary-dist system so I hope this isn't nonsense.

The utils/ghc-cabal/dist-install/build/tmp/ghc-cabal and utils/ghc-pwd/dist-install/build/tmp/ghc-pwd executables have .a extensions, which is a bug, but more importantly are built for arm and thus can't be used.

lukexi@thopminkingscape:~/Code/ghc (ghc-7.8 *=)$ file utils/ghc-cabal/dist-install/build/tmp/ghc-cabal.a
utils/ghc-cabal/dist-install/build/tmp/ghc-cabal.a: Mach-O executable arm

lukexi@thopminkingscape:~/Code/ghc (ghc-7.8 *=)$ file utils/ghc-pwd/dist-install/build/tmp/ghc-pwd.a
utils/ghc-pwd/dist-install/build/tmp/ghc-pwd.a: Mach-O executable arm

So I tried switching them to the inplace/bin/ghc-cabal and utils/ghc-pwd/dist-boot/ghc-pwd copies, respectively, with this patch:
http://lpaste.net/99485

This let me build the .tar.gz without errors, and ./configure it fine, but make install fails here now.
"inplace/bin/ghc-cabal" register libraries/ghc-prim dist-install "/usr/local/lib/arm-apple-darwin10ghc-7.8.20140129/bin/ghc" "/usr/local/lib/arm-apple-darwin10ghc-7.8.20140129/bin/ghc-pkg" "/usr/local/lib/arm-apple-darwin10ghc-7.8.20140129" '' '/usr/local' '/usr/local/lib/arm-apple-darwin10ghc-7.8.20140129' '/usr/local/share/doc/ghc/html/libraries' NO  
ghc-cabal: Bad interface file: dist-install/build/GHC/CString.hi
magic number mismatch: old/corrupt interface file? (wanted 33214052, got
129742)

http://lpaste.net/99486

(looks like a missing dash in the CrossCompilePrefix as well but that's a minor issue)

Does this offer any clues?

Cheers
Luke


On Tue, Feb 4, 2014 at 6:22 PM, Luke Iannini <lukexipd@gmail.com> wrote:
Hi folks,

I'm all set to release binaries for GHC iOS (arm and i386 simulator), but didn't realize the "make binary-dist" machinery is broken for cross-compilers.

I'm starting work on it but will be fumbling in the dark a bit so if anyone has any knowledge or link or ideas on where to look, I'd love to hear them!

Here's the output of "make binary-dist" on a tree after a successful "make" for arm-apple-darwin10 (which will "make install" perfectly).

Cheers
Luke