Add patch to fix libc sysdeps preconfigure on ash.

AS_LINENO_PREPARE was causing an infinitely recursive configure loop.

Before:

    configure: loading cache config.cache
    checking build system type... x86_64-unknown-linux-gnu
    checking host system type... x86_64-unknown-linux-gnu
    checking for gcc... gcc
    checking for suffix of object files... o
    checking whether we are using the GNU C compiler... yes
    checking whether gcc accepts -g... yes
    checking for gcc option to accept ISO C89... none needed
    checking how to run the C preprocessor... cpp
    checking whether we are using the GNU C++ compiler... yes
    checking whether g++ accepts -g... yes
    checking for readelf... readelf
    checking for sysdeps preconfigure fragments... x86_64 configure: WARNING: you should use --build, --host, --target
    configure: WARNING: you should use --build, --host, --target
    checking build system type... (cached) x86_64-unknown-linux-gnu
    checking host system type... (cached) x86_64-unknown-linux-gnu
    checking for dummy-gcc... gcc
    checking for suffix of object files... (cached) o
    checking whether we are using the GNU C compiler... (cached) yes
    checking whether gcc accepts -g... (cached) yes
    checking for gcc option to accept ISO C89... (cached) none needed
    checking how to run the C preprocessor... cpp
    checking whether we are using the GNU C++ compiler... (cached) yes
    checking whether g++ accepts -g... (cached) yes
    checking for dummy-readelf... readelf
    checking for sysdeps preconfigure fragments... x86_64 configure: WARNING: you should use --build, --host, --target
    configure: WARNING: you should use --build, --host, --target
    [...]

After:

    configure: loading cache config.cache
    checking build system type... x86_64-unknown-linux-gnu
    checking host system type... x86_64-unknown-linux-gnu
    checking for gcc... gcc
    checking for suffix of object files... o
    checking whether we are using the GNU C compiler... yes
    checking whether gcc accepts -g... yes
    checking for gcc option to accept ISO C89... none needed
    checking how to run the C preprocessor... cpp
    checking whether we are using the GNU C++ compiler... yes
    checking whether g++ accepts -g... yes
    checking for readelf... readelf
    checking for sysdeps preconfigure fragments... x86_64 checking whether gcc compiles in -mx32 mode by default... no

1 files changed, 51 insertions, 0 deletions

diff --git a/patches/02_fix-preconfigure-on-busybox-ash.patch b/patches/02_fix-preconfigure-on-busybox-ash.patch
new file mode 100644
index 0000000..9c2aacd
--- /dev/null
+++ b/patches/02_fix-preconfigure-on-busybox-ash.patch
@@ -0,0 +1,51 @@
+From: "P. J. McDermott" <pjm@nac.net>
+Description: Fix sysdeps preconfigure fragments on BusyBox ash
+ On shells that don't support the LINENO parameter (e.g. BusyBox ash), the
+ AS_LINENO_PREPARE macro (executed by AC_INIT) preprocesses the script
+ $as_myself into $as_me.lineno.
+ .
+ Unfortunately, when loading sysdeps preconfigure fragements, these as_*
+ parameters refer to the configure script rather than the fragments.
+ .
+ As a result, the configure script is executed by a preconfigure fragment in an
+ infinitely recursive loop.
+ .
+ This patch temporarily changes the parameters to refer to the fragments,
+ allowing the fragments to be properly preprocessed and breaking the loop.
+
+diff -Naur src.orig/libc/aclocal.m4 src/libc/aclocal.m4
+--- src.orig/libc/aclocal.m4	2012-12-02 16:11:45.000000000 -0500
++++ src/libc/aclocal.m4	2013-06-20 12:19:51.818414209 -0400
+@@ -161,7 +161,14 @@
+   for frag in $frags; do
+     name=`echo "$frag" | sed 's@/[[^/]]*[$]@@;s@^.*/@@'`
+     echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
++    orig_as_me=$as_me
++    orig_as_myself=$as_myself
++    as_me=${frag##*/sysdeps/}
++    as_me=${as_me%/preconfigure}-preconfigure
++    as_myself=$frag
+     . "$frag"
++    as_me=$orig_as_me
++    as_myself=$orig_as_myself
+   done
+   AC_MSG_RESULT()
+ fi])
+diff -Naur src.orig/libc/configure src/libc/configure
+--- src.orig/libc/configure	2012-12-02 16:11:45.000000000 -0500
++++ src/libc/configure	2013-06-20 12:24:26.226678382 -0400
+@@ -4000,7 +4000,14 @@
+   for frag in $frags; do
+     name=`echo "$frag" | sed 's@/[^/]*$@@;s@^.*/@@'`
+     echo $ECHO_N "$name $ECHO_C" >&6
++    orig_as_me=$as_me
++    orig_as_myself=$as_myself
++    as_me=${frag##*/sysdeps/}
++    as_me=${as_me%/preconfigure}-preconfigure
++    as_myself=$frag
+     . "$frag"
++    as_me=$orig_as_me
++    as_myself=$orig_as_myself
+   done
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: " >&5
+ $as_echo "" >&6; }