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https://issues.apache.org/jira/browse/HADOOP-8368?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13283694#comment-13283694
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Thomas Graves commented on HADOOP-8368:
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The incompatibility that I would flag is removing the .a files. Or I would
suggest putting them back unless there is reasoning to remove.
I agree that I don't think the build environment qualifies it as an
incompatible change. It would be nice to document though - perhaps in the
twikis and BUILDING.txt. It is fairly obvious when the build fails due to cmake
missing.
> Use CMake rather than autotools to build native code
> ----------------------------------------------------
>
> Key: HADOOP-8368
> URL: https://issues.apache.org/jira/browse/HADOOP-8368
> Project: Hadoop Common
> Issue Type: Improvement
> Affects Versions: 2.0.0-alpha
> Reporter: Colin Patrick McCabe
> Assignee: Colin Patrick McCabe
> Priority: Minor
> Attachments: HADOOP-8368.001.patch, HADOOP-8368.005.patch,
> HADOOP-8368.006.patch, HADOOP-8368.007.patch, HADOOP-8368.008.patch,
> HADOOP-8368.009.patch, HADOOP-8368.010.patch, HADOOP-8368.012.half.patch,
> HADOOP-8368.012.patch, HADOOP-8368.012.rm.patch,
> HADOOP-8368.014.trimmed.patch, HADOOP-8368.015.trimmed.patch,
> HADOOP-8368.016.trimmed.patch, HADOOP-8368.018.trimmed.patch,
> HADOOP-8368.020.rm.patch, HADOOP-8368.020.trimmed.patch,
> HADOOP-8368.021.trimmed.patch
>
>
> It would be good to use cmake rather than autotools to build the native
> (C/C++) code in Hadoop.
> Rationale:
> 1. automake depends on shell scripts, which often have problems running on
> different operating systems. It would be extremely difficult, and perhaps
> impossible, to use autotools under Windows. Even if it were possible, it
> might require horrible workarounds like installing cygwin. Even on Linux
> variants like Ubuntu 12.04, there are major build issues because /bin/sh is
> the Dash shell, rather than the Bash shell as it is in other Linux versions.
> It is currently impossible to build the native code under Ubuntu 12.04
> because of this problem.
> CMake has robust cross-platform support, including Windows. It does not use
> shell scripts.
> 2. automake error messages are very confusing. For example, "autoreconf:
> cannot empty /tmp/ar0.4849: Is a directory" or "Can't locate object method
> "path" via package "Autom4te..." are common error messages. In order to even
> start debugging automake problems you need to learn shell, m4, sed, and the a
> bunch of other things. With CMake, all you have to learn is the syntax of
> CMakeLists.txt, which is simple.
> CMake can do all the stuff autotools can, such as making sure that required
> libraries are installed. There is a Maven plugin for CMake as well.
> 3. Different versions of autotools can have very different behaviors. For
> example, the version installed under openSUSE defaults to putting libraries
> in /usr/local/lib64, whereas the version shipped with Ubuntu 11.04 defaults
> to installing the same libraries under /usr/local/lib. (This is why the FUSE
> build is currently broken when using OpenSUSE.) This is another source of
> build failures and complexity. If things go wrong, you will often get an
> error message which is incomprehensible to normal humans (see point #2).
> CMake allows you to specify the minimum_required_version of CMake that a
> particular CMakeLists.txt will accept. In addition, CMake maintains strict
> backwards compatibility between different versions. This prevents build bugs
> due to version skew.
> 4. autoconf, automake, and libtool are large and rather slow. This adds to
> build time.
> For all these reasons, I think we should switch to CMake for compiling native
> (C/C++) code in Hadoop.
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