Hi, I have a mysterious issue where on OSX I try to build boost 1.77 with among others the json component but it is not built. On linux there is no issue. The same script builds everything fine. Has anybody come across this by any chance ? I could not find anything from a search on the net. Thanks, Jiri Below are more details. Using the commands listed below in the OSX case, the json lib is not built, and on Linux it is. Switching on more verbosity and using the -a -q -d 5 shows that json is in the output, but not clear why it is not built. This also seems to be the case for 1.76, we tried this on multiple machines. export ZLIB_DIR=/tmp/zlib-1.2.11 export BZIP2_DIR=/tmp/bzip2-1.0.6 ./b2 link=static variant=release cxxflags="-fPIC" cflags="-fPIC" --build-type=minimal -j8 --build-dir=/tmp/boost/build stage --stagedir=/tmp/boost/stage -sBZIP2_SOURCE=${BZIP2_DIR} -sZLIB_SOURCE= ${ZLIB_DIR} -sNO_ZSTD=1 --with-filesystem --with-iostreams --with-regex --with-system --with-json ls -l /tmp/boost/stage/lib # osx 10.15.7 clang 12 cmake 3.21.3 $ uname -a Darwin vola-imac-jiri.local 19.6.0 Darwin Kernel Version 19.6.0: Tue Aug 24 20:28:00 PDT 2021; root:xnu-6153.141.40~1/RELEASE_X86_64 x86_64 $ c++ --version Apple clang version 12.0.0 (clang-1200.0.32.29) Target: x86_64-apple-darwin19.6.0 Thread model: posix InstalledDir: /Library/Developer/CommandLineTools/usr/bin $ cmake --version cmake version 3.21.3 $ ll /tmp/boost/stage/lib total 2168 drwxr-xr-x 12 jiri wheel 384 Oct 4 09:10 cmake/ -rw-r--r-- 1 jiri wheel 42688 Oct 4 09:10 libboost_atomic.a -rw-r--r-- 1 jiri wheel 85696 Oct 4 09:10 libboost_bzip2.a -rw-r--r-- 1 jiri wheel 207752 Oct 4 09:10 libboost_filesystem.a -rw-r--r-- 1 jiri wheel 156984 Oct 4 09:10 libboost_iostreams.a -rw-r--r-- 1 jiri wheel 486752 Oct 4 09:10 libboost_regex.a -rw-r--r-- 1 jiri wheel 880 Oct 4 09:10 libboost_system.a -rw-r--r-- 1 jiri wheel 116864 Oct 4 09:10 libboost_zlib.a $ ssh docs # lin gcc10 $ uname -a Linux 09964f3495a3 5.10.25-linuxkit #1 SMP Tue Mar 23 09:27:39 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux $ c++ --version c++ (GCC) 10.3.0 Copyright (C) 2020 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ cmake --version cmake version 3.20.5 $ ls -l /tmp/boost/stage/lib total 2316 drwxr-xr-x 13 vola wheel 4096 Oct 4 12:19 cmake -rw-r--r-- 1 vola wheel 14472 Oct 4 12:19 libboost_atomic.a -rw-r--r-- 1 vola wheel 171174 Oct 4 12:19 libboost_container.a -rw-r--r-- 1 vola wheel 516560 Oct 4 12:19 libboost_filesystem.a -rw-r--r-- 1 vola wheel 226418 Oct 4 12:19 libboost_iostreams.a *-rw-r--r-- 1 vola wheel 478604 Oct 4 12:19 libboost_json.a* -rw-r--r-- 1 vola wheel 797230 Oct 4 12:19 libboost_regex.a -rw-r--r-- 1 vola wheel 1412 Oct 4 12:19 libboost_system.a -rw-r--r-- 1 vola wheel 146394 Oct 4 12:19 libboost_zlib.a