build error for ghc 7.2.1 -- "ghc-pkg: too few bytes"

[gatoatigrado]

Building GHC 7.2.1 fails in Stage 1. I have 7.0.3 installed (also compiled from source). Here's the last few lines from make,

chmod +x inplace/lib/ghc-split
"rm" -f                              inplace/bin/ghc-stage1
echo '#!/bin/sh'                             >> inplace/bin/ghc-stage1
echo 'executablename="/home/gatoatigrado/Downloads/ghc-7.2.1/inplace/lib/ghc-stage1"'            >> inplace/bin/ghc-stage1
echo 'datadir="/home/gatoatigrado/Downloads/ghc-7.2.1/inplace/lib"'       >> inplace/bin/ghc-stage1
echo 'bindir="/home/gatoatigrado/Downloads/ghc-7.2.1/inplace/bin"'        >> inplace/bin/ghc-stage1
echo 'topdir="/home/gatoatigrado/Downloads/ghc-7.2.1/inplace/lib"'     >> inplace/bin/ghc-stage1
echo 'pgmgcc="/usr/bin/gcc"'            >> inplace/bin/ghc-stage1
cat ghc/ghc.wrapper               >> inplace/bin/ghc-stage1
chmod +x                               inplace/bin/ghc-stage1
/usr/bin/gcc -E  -undef -traditional -P -DTOP='"/home/gatoatigrado/Downloads/ghc-7.2.1"'  -x c -Iincludes libffi/package.conf.in -o libffi/package.conf.inplace.raw
grep -v '^#pragma GCC' libffi/package.conf.inplace.raw | sed -e 's/""//g' -e 's/:[   ]*,/: /g' > libffi/package.conf.inplace
"inplace/bin/ghc-pkg" update --force libffi/package.conf.inplace
Reading package info from "libffi/package.conf.inplace" ... done.
ghc-pkg: too few bytes. Failed reading at byte position 44111
make[1]: *** [libffi/package.conf.inplace] Error 1
make[1]: *** Deleting file `libffi/package.conf.inplace'
make: *** [all] Error 2

The output from ./configure is

Configure completed successfully.

   Building GHC version  : 7.2.1

   Build platform        : x86_64-unknown-linux
   Host platform         : x86_64-unknown-linux
   Target platform       : x86_64-unknown-linux

   Bootstrapping using   : /usr/local/bin/ghc
      which is version   : 7.0.3

   Using GCC             : /usr/bin/gcc
      which is version   : 4.5.1

   ld       : /usr/bin/ld
   Happy    : /usr/bin/happy (1.18.5)
   Alex     : /usr/bin/alex (2.3.3)
   Python   : /usr/bin/python
   Perl     : /usr/bin/perl
   dblatex  : /usr/bin/dblatex
   xsltproc : /usr/bin/xsltproc

   HsColour was not found; documentation will not contain source links

   Building DocBook HTML documentation : YES
   Building DocBook PS documentation   : YES
   Building DocBook PDF documentation  : YES
----------------------------------------------------------------------

finally, ghc-pkg check reports no errors.

[igloo]

In HEAD (which will become 7.4) we no longer have libffi/package.conf*.