poky-tiny: Separate the libc features required for meta-toolchain

This fixes bug [YOCTO #2295]

eglibc needs libc-posix-regexp-glibc & libc-libm-big enabled in its
configuration to avoid following eglibc build issue. Thanks to
Nitin for identifying the required features.

    ...
    | In file included from xregex.c:634:0:
    | xregex.c: In function 'byte_regex_compile':
    | xregex.c:3395:8: error: too few arguments to function 'findidx'
    | ../locale/weight.h:23:1: note: declared here
    ...

The libc features added to support building meta-toolchain add 461KB to the C
libraries. 320KB directly to libc (a 32% increase in size). If not building
meta-toolchain, the user should be able to easily configure these out.

Create a new variable to capture these dependencies,
DISTRO_FEATURES_LIBC_TOOLCHAIN, keeping them separate from the core tiny
requirements. Make it clear how to disable these if meta-toolchain is not
needed.

This patch has been tested by running the following for the qemux86 machine with
DISTRO=poky-tiny:

    $ bitbake -c cleansstate eglibc
    $ bitbake meta-toolchain
    $ bitbake core-image-minimal

The libc comparisons were made from core-image-minimal ext2 filesystems build
before and after the applicaiton of this patch and Nitin's previous poky-tiny
libc features patch in support of meta-toolchain:

    commit 8c48ab6183934fd32600997cc33e0cd3bf63139b
    Author: Nitin A Kamble <nitin.a.kamble@intel.com>
    Date:   Mon Apr 9 15:15:01 2012 -0700

        poky-tiny.conf: adjust eglibc options for poky-tiny

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Nitin A. Kamble <nitin.a.kamble@intel.com>
CC: Saul Wold <sgw@linux.intel.com>
CC: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 12 insertions, 6 deletions

diff --git a/meta-yocto/conf/distro/poky-tiny.conf b/meta-yocto/conf/distro/poky-tiny.conf
index 58d64ece35..327cc1ee2c 100644
--- a/meta-yocto/conf/distro/poky-tiny.conf
+++ b/meta-yocto/conf/distro/poky-tiny.conf
@@ -63,12 +63,17 @@ ASSUME_PROVIDED += "pkgconfig$"
 # Reconfigure eglibc for a smaller installation
 # Comment out any of the lines below to disable them in the build
 DISTRO_FEATURES_LIBC_TINY = "libc-libm libc-crypt"
-# for gettext
-DISTRO_FEATURES_LIBC_TINY += "libc-posix-clang-wchar"
-# for m4
-DISTRO_FEATURES_LIBC_TINY += "libc-spawn libc-locale-code"
-# for elfutils
-DISTRO_FEATURES_LIBC_TINY += "libc-ftraverse"
+
+# Building meta-toolchain currently imposes some additional requirements:
+# If you do not plan to build meta-toolchain, you can save ~461KB by
+# commenting out the DISTRO_FEATURES_LIBC_TOOLCHAIN assignment
+# gettext needs wchar, m4 needs spawn and locale, elfutils needs ftraverse
+DISTRO_FEATURES_LIBC_TOOLCHAIN = "libc-posix-clang-wchar \
+                                  libc-spawn libc-locale-code \
+                                  libc-ftraverse libc-libm-big \
+                                  libc-posix-regexp-glibc \
+                                 "
+
 # Required for "who"
 DISTRO_FEATURES_LIBC_MINIMAL = "libc-utmp libc-getlogin"
 DISTRO_FEATURES_LIBC_REGEX = "libc-posix-regexp"
@@ -78,6 +83,7 @@ DISTRO_FEATURES_LIBC = "${DISTRO_FEATURES_LIBC_TINY} \
                         ${DISTRO_FEATURES_LIBC_MINIMAL} \
                         ${DISTRO_FEATURES_LIBC_REGEX} \
                         ${DISTRO_FEATURES_LIBC_NET} \
+                        ${DISTRO_FEATURES_LIBC_TOOLCHAIN} \
                        "
 
 # Comment out any of the lines below to disable them in the build