uboot-mt623x/lib/lzma
Sebastien Carlier 6d8962e814 Switch from archive libraries to partial linking
Before this commit, weak symbols were not overridden by non-weak symbols
found in archive libraries when linking with recent versions of
binutils.  As stated in the System V ABI, "the link editor does not
extract archive members to resolve undefined weak symbols".

This commit changes all Makefiles to use partial linking (ld -r) instead
of creating library archives, which forces all symbols to participate in
linking, allowing non-weak symbols to override weak symbols as intended.
This approach is also used by Linux, from which the gmake function
cmd_link_o_target (defined in config.mk and used in all Makefiles) is
inspired.

The name of each former library archive is preserved except for
extensions which change from ".a" to ".o".  This commit updates
references accordingly where needed, in particular in some linker
scripts.

This commit reveals board configurations that exclude some features but
include source files that depend these disabled features in the build,
resulting in undefined symbols.  Known such cases include:
- disabling CMD_NET but not CMD_NFS;
- enabling CONFIG_OF_LIBFDT but not CONFIG_QE.

Signed-off-by: Sebastien Carlier <sebastien.carlier@gmail.com>
2010-11-17 21:02:18 +01:00
..
LzmaDec.c Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
LzmaDec.h Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
LzmaTools.c Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
LzmaTools.h Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
Makefile Switch from archive libraries to partial linking 2010-11-17 21:02:18 +01:00
README.txt Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
Types.h Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
history.txt Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
import_lzmasdk.sh Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
license.txt Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00
lzma.txt Rename lib_generic/ to lib/ 2010-04-13 09:13:04 +02:00

README.txt

The lib_lzma functionality was written by Igor Pavlov.
The original source cames from the LZMA SDK web page:

URL: 		http://www.7-zip.org/sdk.html
Author:         Igor Pavlov

The import is made using the import_lzmasdk.sh script that:

* untars the lzmaXYY.tar.bz2 file (from the download web page)
* copies the files LzmaDec.h, Types.h, LzmaDec.c, history.txt,
  and lzma.txt from source archive into the lib_lzma directory (pwd).

Example:

 . import_lzmasdk.sh ~/lzma465.tar.bz2

Notice: The files from lzma sdk are _not modified_ by this script!

The files LzmaTools.{c,h} are provided to export the lzmaBuffToBuffDecompress()
function that wraps the complex LzmaDecode() function from the LZMA SDK. The
do_bootm() function uses the lzmaBuffToBuffDecopress() function to expand the
compressed image.

The directory U-BOOT/include/lzma contains stubs files that permit to use the
library directly from U-BOOT code without touching the original LZMA SDK's
files.

Luigi 'Comio' Mantellini <luigi.mantellini@idf-hit.com>