In the book "Embedded Linux Systems with the Yocto Project", Chapter 4 contains a sample called "HelloWorld - BitBake style". I encountered a bunch of problems trying to get the old example working against the "Sumo" release 2.5.
If you're like me, the first error you encountered following the book's instructions was that you copied across bitbake.conf and got:
ERROR: ParseError at /tmp/bbhello/conf/bitbake.conf:749: Could not include required file conf/abi_version.conf
And after copying over abi_version.conf as well, you kept finding more and more cross-connected files that needed to be moved, and then some relative-path errors after that... Is there a better way?
Here's a series of steps which can allow you to bitbake nano based on the book's instructions.
Unless otherwise specified, these samples and instructions are all based on the online copy of the book's code-samples. While convenient for copy-pasting, the online resource is not totally consistent with the printed copy, and contains at least one extra bug.
Initial workspace setup
This guide assumes that you're working with Yocto release 2.5 ("sumo"), installed into /tmp/poky, and that the build environment will go into /tmp/bbhello. If you don't the Poky tools+libraries already, the easiest way is to clone it with:
$ git clone -b sumo git://git.yoctoproject.org/poky.git /tmp/poky
Then you can initialize the workspace with:
$ source /tmp/poky/oe-init-build-env /tmp/bbhello/
If you start a new terminal window, you'll need to repeat the previous command which will get get your shell environment set up again, but it should not replace any of the files created inside the workspace from the first time.
Wiring up the defaults
The oe-init-build-env script should have just created these files for you:
bbhello/conf/local.conf
bbhello/conf/templateconf.cfg
bbhello/conf/bblayers.conf
Keep these, they supersede some of the book-instructions, meaning that you should not create or have the files:
bbhello/classes/base.bbclass
bbhello/conf/bitbake.conf
Similarly, do not overwrite bbhello/conf/bblayers.conf with the book's sample. Instead, edit it to add a single line pointing to your own meta-hello folder, ex:
BBLAYERS ?= " \
${TOPDIR}/meta-hello \
/tmp/poky/meta \
/tmp/poky/meta-poky \
/tmp/poky/meta-yocto-bsp \
"
Creating the layer and recipe
Go ahead and create the following files from the book-samples:
meta-hello/conf/layer.conf
meta-hello/recipes-editor/nano/nano.bb
We'll edit these files gradually as we hit errors.
Can't find recipe error
The error:
ERROR: BBFILE_PATTERN_hello not defined
It is caused by the book-website's bbhello/meta-hello/conf/layer.conf being internally inconsistent. It uses the collection-name "hello" but on the next two lines uses _test suffixes. Just change them to _hello to match:
# Set layer search pattern and priority
BBFILE_COLLECTIONS += "hello"
BBFILE_PATTERN_hello := "^${LAYERDIR}/"
BBFILE_PRIORITY_hello = "5"
Interestingly, this error is not present in the printed copy of the book.
No license error
The error:
ERROR: /tmp/bbhello/meta-hello/recipes-editor/nano/nano.bb: This recipe does not have the LICENSE field set (nano)
ERROR: Failed to parse recipe: /tmp/bbhello/meta-hello/recipes-editor/nano/nano.bb
Can be fixed by adding a license setting with one of the values that bitbake recognizes. In this case, add a line onto nano.bb of:
LICENSE="GPLv3"
Recipe parse error
ERROR: ExpansionError during parsing /tmp/bbhello/meta-hello/recipes-editor/nano/nano.bb
[...]
bb.data_smart.ExpansionError: Failure expanding variable PV_MAJOR, expression was ${#bb.data.getVar('PV',d,1).split('.')[0]} which triggered exception AttributeError: module 'bb.data' has no attribute 'getVar'
This is fixed by updating the special python commands being used in the recipe, because #bb.data was deprecated and is now removed. Instead, replace it with #d, ex:
PV_MAJOR = "${#d.getVar('PV',d,1).split('.')[0]}"
PV_MINOR = "${#d.getVar('PV',d,1).split('.')[1]}"
License checksum failure
ERROR: nano-2.2.6-r0 do_populate_lic: QA Issue: nano: Recipe file fetches files and does not have license file information (LIC_FILES_CHKSUM) [license-checksum]
This can be fixed by adding a directive to the recipe telling it what license-info-containing file to grab, and what checksum we expect it to have.
We can follow the way the recipe generates the SRC_URI, and modify it slightly to point at the COPYING file in the same web-directory. Add this line to nano.bb:
LIC_FILES_CHKSUM = "${SITE}/v${PV_MAJOR}.${PV_MINOR}/COPYING;md5=f27defe1e96c2e1ecd4e0c9be8967949"
The MD5 checksum in this case came from manually downloading and inspecting the matching file.
Done!
Now bitbake nano ought to work, and when it is complete you should see it built nano:
/tmp/bbhello $ find ./tmp/deploy/ -name "*nano*.rpm*"
./tmp/deploy/rpm/i586/nano-dbg-2.2.6-r0.i586.rpm
./tmp/deploy/rpm/i586/nano-dev-2.2.6-r0.i586.rpm
I have recently worked on that hands-on hello world project. As far as I am concerned, I think that the source code in the book contains some bugs. Below there is a list of suggested fixes:
Inheriting native class
In fact, when you build with bitbake that you got from poky, it builds only for the target, unless you mention in your recipe that you are building for the host machine (native). You can do the latter by adding this line at the end of your recipe:
inherit native
Adding license information
It is worth mentioning that the variable LICENSE is important to be set in any recipe, otherwise bitbake rises an error. In our case, we try to build the version 2.2.6 of the nano editor, its current license is GPLv3, hence it should be mentioned as follow:
LICENSE = "GPLv3"
Using os.system calls
As the book states, you cannot dereference metadata directly from a python function. Which means it is mandatory to access metadata through the d dictionary. Bellow, there is a suggestion for the do_unpack python function, you can use its concept to code the next tasks (do_configure, do_compile):
python do_unpack() {
workdir = d.getVar("WORKDIR", True)
dl_dir = d.getVar("DL_DIR", True)
p = d.getVar("P", True)
tarball_name = os.path.join(dl_dir, p+".tar.gz")
bb.plain("Unpacking tarball")
os.system("tar -x -C " + workdir + " -f " + tarball_name)
bb.plain("tarball unpacked successfully")
}
Launching the nano editor
After successfully building your nano editor package, you can find your nano executable in the following directory in case you are using Ubuntu (arch x86_64):
./tmp/work/x86_64-linux/nano/2.2.6-r0/src/nano
Should you have any comments or questions, Don't hesitate !
Using Cudafy version 1.29, which can be downloaded from here
I am executing the examples that are found in the install folder CudafyV1.29\CudafyByExample\
Specifically, "chapter 3" example that begins line 42 of program.cs calls the following:
simple_kernel.Execute();
which is this:
public static void Execute()
{
CudafyModule km = CudafyTranslator.Cudafy(); // <--exception thrown!
GPGPU gpu = CudafyHost.GetDevice(CudafyModes.Target, CudafyModes.DeviceId);
gpu.LoadModule(km);
gpu.Launch().thekernel(); // or gpu.Launch(1, 1, "kernel");
Console.WriteLine("Hello, World!");
}
The indicated line throws this exception:
Compilation error: CUDAFYSOURCETEMP.cu
'C:\Program' is not recognized as an internal or external command,
operable program or batch file. .
Which is immediately obvious that the path has spaces and the programmer did not double quote or use ~ to make it operational.
So, I did not write this code. And I cannot step through the sealed code contained within CudafyModule km = CudafyTranslator.Cudafy();In fact I don't even know the full path that is causing the exception, it is cut-off in the exception message.
Does anyone have a suggestion for how to fix this issue?
Update #1: I discovered where CUDAFYSOURCETEMP.cu lives on my computer, here it is:
C:\Users\humphrt\Desktop\Active Projects\Visual Studio
Projects\CudafyV1.29\CudafyByExample\bin\Debug
...I'm still trying to determine what the program is looking for along the path to 'C:\Program~'.
I was able to apply a workaround to bypass this issue. The workaround is to reinstall all components of cudafy in to folders with paths with no ' ' (spaces). My setup looks like the below screenshot. Notice that I also installed the CUDA TOOLKIT from NVIDIA in the same folder - also with no spaces in folder names.
I created a folder named "C:\CUDA" and installed all components within it, here is the folder structure:
My CMake code looks like the following:
macro(macro_name target_name)
add_custom_command(TARGET ${target_name}
POST_BUILD
COMMAND MyCommand)
endmacro()
Running this I get the following message:
CMake Warning (dev) at ... (add_custom_command):
Policy CMP0040 is not set: The target in the TARGET signature of
add_custom_command() must exist. Run "cmake --help-policy CMP0040" for
policy details. Use the cmake_policy command to set the policy and
suppress this warning.
The target name "target_name" is unknown in this context.
The same code inside of a function works great but I need macro for other things.
CMake policy (http://www.cmake.org/cmake/help/v3.0/policy/CMP0040.html) suggests just ignoring of this warning (and ignoring of adding of postbuild step at all) or treating it as error depending on the settings.
This: http://www.cmake.org/cmake/help/v3.0/command/macro.html states that parameters behavior in macros is different from one in functions.
How do I properly refer to macro parameters to get this work?
I've managed to figure out the reason: in my case wrong directory was used as ${CMAKE_CURRENT_BINARY_DIR} inside of the macro. Fixing paths allowed to get desirable result
I am new to S-Functions and Real TIme WorkShop. The S-Function has been created using an Embedded Matlab Function. The S-Function Works fine, but when i try to build the same, i get the following error report:
It appears that the build process was unable to locate some utility (e.g. make, compiler, linker, etc.). Please verify your path and tool environment variables are correct. You should be able to execute the make command: .\Radius_S_func2.bat at an MS DOS Command Prompt in the directory: C:\Users\skaushik\Desktop\Matlab Models\WIP\TESTs\Sfunc_2\Radius_S_func2_Source Currently, this generates the following error:
C:\Users\skaushik\Desktop\Matlab Models\WIP\TESTs\Sfunc_2\Radius_S_func2_Source>set MATLAB=C:\MATLAB\R2010b
C:\Users\skaushik\Desktop\Matlab Models\WIP\TESTs\Sfunc_2\Radius_S_func2_Source>.......\u_Utils\Build\make -f Radius_S_func2.mk GENERATE_REPORT=0 INCLUDE_MDL_TERMINATE_FCN=0 COMBINE_OUTPUT_UPDATE_FCNS=1 MAT_FILE=0 MULTI_INSTANCE_CODE=0 INTEGER_CODE=0 PORTABLE_WORDSIZES=0 GENERATE_ERT_S_FUNCTION=0 GENERATE_ASAP2=0 EXT_MODE=0 EXTMODE_STATIC_ALLOC=0 EXTMODE_STATIC_ALLOC_SIZE=1000000 EXTMODE_TRANSPORT=0 TMW_EXTMODE_TESTING=0 MODELLIB=Radius_S_func2lib.lib RELATIVE_PATH_TO_ANCHOR=.. MODELREF_TARGET_TYPE=NONE OPTS="-DRT -DUSE_RTMODEL -DERT" The system cannot find the path specified.
PLease guide me how to understand the error, so i can take care of it myself.
Thank you!!
Solution: The build target was not specified therefore matlab gave the above mentioned error. To resolve this one should specify the build environment for a specific target.
Description Resource Path Location Type
make: * Config file '' does not exist -- add the OMNeT++ bin directory to the path so that opp_configfilepath can be found, or set the OMNETPP_CONFIGFILE variable to point to Makefile.inc. Stop. Makefile /IWF line 55 C/C++ Problem**
I had the same problem with OMNET++ 4.3.1, it turns out that i extracted the omnet source files to C:\Omnet rather than the default expected location c:/omnetpp-4.3.1 by the make script. So when you try to build the mixim, the build stops by giving two errors one of them being
make: *** Config file 'c:/omnetpp-4.3.1/Makefile.inc' does not exist --
To solve this issue, navigate to mixim(or whatever folder)>out>gcc-debug>.last-copts or you can search your workspace for something like omnetpp-4.3.1, remember the version, to locate the file. Then just change -Ic:/omnetpp-4../include to exact directory path where you have extracted omnet++.