6453276414
Commit a2546fae [ftrace: Add -mfentry to Makefile on function tracer]
adds support for using -mfentry when possible, whenever the ftrace
CONFIG_FUNCTION_TRACER option is enabled.
This unfortunately causes bogus dwarf debuginfo to be generated:
gcc Bug 54793 - the location of a formal_parameter is not started from a
function entry with -mfentry
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54793
This can be fixed by applying the gcc patch above, which will be
present in gcc-4.8, but in the meantime, the problem is currently
being worked around in different ways by various tools. One of those
tools that we support in Yocto, Systemtap, requires the DW_AT_producer
string contain -mfentry, which means that it's assuming
record-gcc-switches is also used:
SystemTap Bug 15123 - workaround for bad debuginfo for -mfentry
http://sourceware.org/bugzilla/show_bug.cgi?id=15123
The lack of -grecord-gcc-switches and therefore a missing -mfentry
string in Yocto leads to the following Yocto bug:
Bug 4099 - Crosstap script check fails
https://bugzilla.yoctoproject.org/show_bug.cgi?id=4099
Which is what this patch intends to fix.
It only affects architectures that HAVE_FENTRY when
CONFIG_FUNCTION_TRACER is turned on and in any case is just adding to
the debuginfo, so there doesn't seem to be much risk to adding it.
(From OE-Core rev: c04f611aa4bf77867fe78a005d09434226feb62c)
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a complete prepackaged build system and development environment. It features support for building customised embedded device style images. There are reference demo images featuring a X11/Matchbox/GTK themed UI called Sato. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK with IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of layers which extend the systems capabilities in a modular way.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation and various sources of information e.g. for the hardware support. Poky is in turn a component of the Yocto Project.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at: http://yoctoproject.org/documentation
OpenEmbedded-Core is a layer containing the core metadata for current versions of OpenEmbedded. It is distro-less (can build a functional image with DISTRO = "") and contains only emulated machine support.
For information about OpenEmbedded, see the OpenEmbedded website: http://www.openembedded.org/
Where to Send Patches
As Poky is an integration repository, patches against the various components should be sent to their respective upstreams.
bitbake: bitbake-devel@lists.openembedded.org
meta-yocto: poky@yoctoproject.org
Most everything else should be sent to the OpenEmbedded Core mailing list. If in doubt, check the oe-core git repository for the content you intend to modify. Before sending, be sure the patches apply cleanly to the current oe-core git repository. openembedded-core@lists.openembedded.org
Note: The scripts directory should be treated with extra care as it is a mix of oe-core and poky-specific files.