Cannot disable zstd with "bjam -sNO_ZSTD" in boost/1.78.0

1. The integration of bzip2 and zlib is much better in iostreams than the integration of lzma and zstd. There is a need to build boost iostreams with sandboxed versions of all the compressors instead of having bjam find and build against the host OS versions of these

2. There is no equivalent of ZLIB_SOURCE/BZIP2_SOURCE for LZMA_SOURCE/ZSTD_SOURCE ??

3. How do I redirect the boost iostreams build to use specific versions of LZMA and ZSTD during boost iostreams build?

4. bjam -sNO_ZSTD does not work
./tools/build/src/engine/bjam -d+2 **-sNO_ZSTD** --debug-configuration variant=debug toolset=gcc address-model=64 visibility=global cxxflags='--std=c++11 -fPIC -ggdb3 -O0' install --prefix=./sles11_x86_64_gcc4.7.2/deb/boost_1_78_0 --stagedir=./sles11_x86_64_gcc4.7.2/deb/boost_1_78_0-build --includedir=./sles11_x86_64_gcc4.7.2/deb/boost_1_78_0/include --libdir=./sles11_x86_64_gcc4.7.2/deb/boost_1_78_0/lib --with-atomic --with-chrono --with-container --with-context --with-contract --with-coroutine --with-date_time --with-exception --with-fiber --with-filesystem --with-graph --with-graph_parallel --with-headers --with-iostreams --with-locale --with-log --with-math --with-mpi --with-program_options --with-random --with-regex --with-serialization --with-stacktrace --with-system --with-test --with-thread --with-timer --with-type_erasure --with-json --with-python
....
notice: [zstd] Using pre-installed library
notice: [zstd] Condition
...
- zstd : yes
...

which leads to the inevitable linker errors

-I-:/nfs/site/itools/em64t_SLES12SP5/pkgs/gcc/4.7.2/.bin/../lib64/gcc/x86_64-suse-linux/4.7.2/../../../../x86_64-suse-linux/bin/ld: warning: libzstd.so.1, needed by
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so, not found (try using -rpath or -rpath-link)
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_freeCStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `lzma_stream_decoder@XZ_5.0'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_getErrorName'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_createDStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_freeDStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_compressStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_decompressStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `lzma_code@XZ_5.0'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `ZSTD_initCStream'
./boost/1.78.0/libs/sles12_x86_64_gcc4.7.2/opt/libboost_iostreams.so: undefined reference to `lzma_stream_encoder_mt

Start by reproducing the provided Boost 1.78.0 build command with -sNO_ZSTD and inspect the zstd configuration used by the Boost iostreams build. Done means disabling zstd no longer selects the pre-installed library or produces zstd linker references; the issue mentions tools/build/src/engine/bjam as the build entry point.

Written by the indexing model from the issue text.