Boost fails to build when path contains % (percent sign)

[yury.zaytsev@…]

Ubuntu 14.04, Boost 1.61.0:

zaytsev@work:~/src/boost/bad%path/boost_1_61_0$ ./bootstrap.sh --prefix=$(pwd)/../install
Building Boost.Build engine with toolset gcc... tools/build/src/engine/bin.linuxx86_64/b2
Detecting Python version... 2.7
Detecting Python root... /usr
Unicode/ICU support for Boost.Regex?... not found.
Generating Boost.Build configuration in project-config.jam...

Bootstrapping is done. To build, run:

    ./b2
    
To adjust configuration, edit 'project-config.jam'.
Further information:

   - Command line help:
     ./b2 --help
     
   - Getting started guide: 
     http://www.boost.org/more/getting_started/unix-variants.html
     
   - Boost.Build documentation:
     http://www.boost.org/build/doc/html/index.html

zaytsev@work:~/src/boost/bad%path/boost_1_61_0$ ./b2 install
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/kernel/modules.jam:107: in modules.call-in
ERROR: rule "<abi>sysv" unknown in root module.
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/util/indirect.jam:98: in indirect.call
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:1054: in evaluate-requirements
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:1112: in common-properties2
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:977: in targets.common-properties
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:1303: in alias-target-class.generate
/home/zaytsev/src/boost/bad%path/boost_1_61_0/boostcpp.jam:432: in build-multiple
/home/zaytsev/src/boost/bad%path/boost_1_61_0/boostcpp.jam:394: in class@top-level-target.generate
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:774: in generate-really
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build/targets.jam:746: in class@main-target.generate
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/build-system.jam:714: in load
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/kernel/modules.jam:295: in import
/home/zaytsev/src/boost/bad%path/boost_1_61_0/tools/build/src/kernel/bootstrap.jam:139: in boost-build
/home/zaytsev/src/boost/bad%path/boost_1_61_0/boost-build.jam:17: in module scope

[anonymous]

If you are interested how come I ended up with such weird build directory paths, have a look at this related issue:

​https://issues.jenkins-ci.org/browse/JENKINS-34564

Since recently, Jenkins generates such paths for the builds, because they opted to use URL encoding scheme to mangle potentially problematic characters, like "/".