Reading through make documentation, seems setting -jx to MAKEFLAGS is a no-op.<br><br><i>"The <samp>`-j'</samp> option is a special case (see section <a href="http://theory.uwinnipeg.ca/localfiles/infofiles/make/make_47.html#SEC46">Parallel Execution</a>).
If you set it to some numeric value, <samp>`-j 1'</samp> is always put into
<code>MAKEFLAGS</code> instead of the value you specified. This is because if
the <samp>`-j'</samp> option were passed down to sub-<code>make</code>s, you would
get many more jobs running in parallel than you asked for. If you give
<samp>`-j'</samp> with no numeric argument, meaning to run as many jobs as
possible in parallel, this is passed down, since multiple infinities are
no more than one.
"</i><br><br>Source: <a href="http://theory.uwinnipeg.ca/localfiles/infofiles/make/make_53.html">http://theory.uwinnipeg.ca/localfiles/infofiles/make/make_53.html</a><br><br>Jc<br><br><div class="gmail_quote">On Fri, Sep 9, 2011 at 3:37 PM, Mike Wittman <span dir="ltr"><<a href="mailto:michael.wittman@headwave.com">michael.wittman@headwave.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><u></u>
<div bgcolor="#ffffff" text="#000000">
If you are building on Linux, try<br>
MAKEFLAGS=j8 make distcheck<br>
<br>
I have successfully used the MAKEFLAGS environment variable to
propagate parallel build invocations through scripts that invoke
make with fixed options.<br>
<br>
-Mike<div><div></div><div class="h5"><br>
<br>
On 09/09/2011 09:21 AM, Clifford Yapp wrote:
</div></div><blockquote type="cite"><div><div></div><div class="h5">I can finally give a good concrete case where I might
need to do this (or need some other very clever solution).<br>
<br>
I have created a distcheck command for BRL-CAD that has a lot of
responsibilities, including doing a complete configure and build
of BRL-CAD from a source archive expanded from a CPack tarball.
The distcheck rule uses cmake to fire off the build (this is to
try and be future proof against using other tools than Make to do
a distcheck) but I need to pass the parallel build setting -j from
Make down to the ${CMAKE_COMMAND} build launched by the distcheck
rule, and there doesn't seem to be any way to do it.<br>
<br>
This is the subset of the distcheck rule (somewhat edited for
clarity):<br>
<br>
ADD_CUSTOM_TARGET(distcheck<br>
COMMAND ${CMAKE_COMMAND} -E echo "Stage 1: Create source
tgz, tbz2 and zip archives from toplevel archive."<br>
COMMAND cpack --config
${CMAKE_CURRENT_BINARY_DIR}/CPackSourceConfig.cmake<br>
COMMAND ${CMAKE_COMMAND} -E echo "Stage 2: Expand tgz
archive and prepare to build from archive sources."<br>
COMMAND ${CMAKE_COMMAND} -E tar xvzf
${CPACK_SOURCE_PACKAGE_FILE_NAME}.tar.gz<br>
COMMAND ${CMAKE_COMMAND} -E make_directory
_${CPACK_SOURCE_PACKAGE_FILE_NAME}-build<br>
COMMAND ${CMAKE_COMMAND} -E make_directory
_${CPACK_SOURCE_PACKAGE_FILE_NAME}-install<br>
COMMAND ${CMAKE_COMMAND} -E chdir
_${CPACK_SOURCE_PACKAGE_FILE_NAME}-build ${CMAKE_COMMAND}
../${CPACK_SOURCE_PACKAGE_FILE_NAME}
-DCMAKE_INSTALL_PREFIX=${CMAKE_CURRENT_BINARY_DIR}/_${CPACK_SOURCE_PACKAGE_FILE_NAME}-install<br>
COMMAND ${CMAKE_COMMAND} -E echo "Stage 3: Compile using
source from tgz archive."<br>
COMMAND ${CMAKE_COMMAND} --build
_${CPACK_SOURCE_PACKAGE_FILE_NAME}-build<br>
)<br>
<br>
This can be successfully fired off by "make distcheck", which is
the desired behavior. However, the --build option doesn't respect
(naturally) any -jN options fed to make, since they aren't
specified at CMake time when the distcheck Makefile target is
being generated. <br>
<br>
Perversely enough, if I'm understanding the issue correctly I
won't be able to use the -jN value itself in any case, even if the
Makefile can be taught to do something smart: <a href="http://old.nabble.com/MAKEFLAGS-var-does-not-show-%22-j%22-param-----td15983337.html" target="_blank">http://old.nabble.com/MAKEFLAGS-var-does-not-show-%22-j%22-param-----td15983337.html</a><br>
<br>
The best idea I can come up with so far is for the CMake generated
Makefile to write out a variable containing some CPU related
variable (e.g. make CPUS=8 and write the value of $(CPUS) to
CMakeFiles/make_cpu_flag or some such) and then convert the
distcheck commands above into a series of EXECUTE_PROCESS lines in
a rundistcheck.cmake file that is launched by the distcheck rule
with a ${CMAKE_COMMAND}. In rundistcheck.cmake, I can check for
the presence of the make_cpu_flag file and if found add the -j
parallel flag to the --build line before running it. That will
mean a parallel distcheck will have to use a different make syntax
than the standard make -j, but at least it would be something.
Unfortunately, that means I still need the Makefile to let me know
what was passed in up front, which means tweaking the CMake
generated output somehow (not really sure how yet).<br>
<br>
Does anybody else have a mechanism for passing parallel build
instructions from make down to child ${CMAKE_COMMAND} --build
instances?<br>
<br>
Cheers,<br>
CY<br>
<br>
<br>
<div class="gmail_quote">On Wed, Feb 2, 2011 at 4:32 PM, Michael
Hertling <span dir="ltr"><<a href="mailto:mhertling@online.de" target="_blank">mhertling@online.de</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div>
<div>On 02/02/2011 03:34 PM, Clifford Yapp wrote:<br>
> Is there any way to customize the Makefile output
from CMake to<br>
> include user-defined lines (say, something like
"#include<br>
> Makefile.inc") at the end of each Make file?<br>
</div>
</div>
</blockquote>
<div><br>
[snip]<br>
</div>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">However, this approach is neither portable
nor clean<br>
nor <your-expectation-here>, so I would ask Eric's
questions, too. ;)<br>
<br>
Regards,<br>
<br>
Michael<br>
</blockquote>
</div>
<br>
</div></div><pre><fieldset></fieldset>
_______________________________________________
Powered by <a href="http://www.kitware.com" target="_blank">www.kitware.com</a><div class="im">
Visit other Kitware open-source projects at <a href="http://www.kitware.com/opensource/opensource.html" target="_blank">http://www.kitware.com/opensource/opensource.html</a>
Please keep messages on-topic and check the CMake FAQ at: <a href="http://www.cmake.org/Wiki/CMake_FAQ" target="_blank">http://www.cmake.org/Wiki/CMake_FAQ</a>
Follow this link to subscribe/unsubscribe:
<a href="http://www.cmake.org/mailman/listinfo/cmake" target="_blank">http://www.cmake.org/mailman/listinfo/cmake</a></div></pre>
</blockquote>
<br>
</div>
<br>_______________________________________________<br>
Powered by <a href="http://www.kitware.com" target="_blank">www.kitware.com</a><br>
<br>
Visit other Kitware open-source projects at <a href="http://www.kitware.com/opensource/opensource.html" target="_blank">http://www.kitware.com/opensource/opensource.html</a><br>
<br>
Please keep messages on-topic and check the CMake FAQ at: <a href="http://www.cmake.org/Wiki/CMake_FAQ" target="_blank">http://www.cmake.org/Wiki/CMake_FAQ</a><br>
<br>
Follow this link to subscribe/unsubscribe:<br>
<a href="http://www.cmake.org/mailman/listinfo/cmake" target="_blank">http://www.cmake.org/mailman/listinfo/cmake</a><br></blockquote></div><br><br clear="all"><br>-- <br>+1 919 869 8849<br><br>