This document describes how libmysqlclient was packaged for build2. In particular, this understanding will be useful when upgrading to a new upstream version. See ../README-DEV for general notes on MySQL packaging. Symlink the required upstream components and provide our own implementations for auto-generated headers: $ ln -s ../upstream/LICENSE $ ln -s ../../upstream/{extra/zlib,strings,vio,sql-common,sql,mysys,mysys_ssl,libbinlogevents,libmysql} \ mysql $ ln -s ../../upstream/include mysql/mysql Note that we unable to generate mysql_version.h directly from the template as it is included as "mysql_version.h" in upstream's source code, which makes impossible using the header-generating machinery. That's why we create mysql/mysql_version.h that includes that we auto-generate from upstream's mysql/mysql_version.h.in. $ ln -s zlib/zconf.h.cmakein mysql/zconf.h.cmakein.orig Use mysql/zconf.h.cmakein.orig for creating mysql/zconf.h manually, defining/undefining macros introduced with #cmakedefine. $ ln -s libbinlogevents/binlog_config.h.cmake mysql/binlog_config.h.cmake.orig Use mysql/binlog_config.h.cmake.orig for creating mysql/binlog_config.h manually, defining/undefining macros introduced with #cmakedefine. $ ln -s ../../upstream/config.h.cmake mysql/config.h.cmake.orig Use mysql/config.h.cmake.orig for creating mysql/my_config.h and mysql/config.h.in, defining/undefining macros introduced with #cmakedefine. Most of the macro values in mysql/my_config.h can be determined at the preprocessing time using the pre-defined macros. To obtain the pre-defined macros for gcc and clang run: $ gcc -dM -E - < /dev/null $ clang -dM -E - < /dev/null Some macro values can not be easily determined at the preprocessing time. We define them based on the supported platform tests and add mysql/assert.c, containing compile-time assertions for the macros in question. mysql/config.h.in defines macros that depend on the version and build2 configuration variables. Note that if it is uneasy to define a macro, you may check if you really need to, grepping for its usages, for example: grep -e CPU_LEVEL1_DCACHE_LINESIZE `find -L . -name '*.c*' -o -name '*.h*'` And it may become obvious that the macro is not used in libmysqlclient. Re-creating mysql/my_config.h from scratch every time we upgrade to a new upstream version would be a real pain. Instead we can only (un)define the newly introduced macros, comparing the already defined and currently used macro sets: $ for m in `cat mysql/{config,binlog_config}.h.cmake.orig | \ sed -n 's/.*#\s*\(define\|cmakedefine\)\s\{1,\}\([_a-zA-Z0-9]\{1,\}\)\(\s.*\)\{0,1\}$/\2/p' | sort -u`; do if grep -q -e "\b$m\b" `find -L . -name '*.h' -a ! -name my_config.h -a ! -name config.h -o -name '*.c' -o -name '*.cc' -a ! -name mysqld.cc -o -name '*.cpp' -o -name '*.hpp'`; then echo "$m" fi done >used-macros $ cat mysql/my_config.h mysql/config.h.in mysql/binlog_config.h | sed -n 's/#\s*\(define\|undef\)\s\{1,\}\([_a-zA-Z0-9]\{1,\}\)\(\s.*\)\{0,1\}$/\2/p' | sort -u >defined-macros $ diff defined-macros used-macros >diff-macros Create mysql/libmysql_exports.def, containing the exported names list. For that purpose grep through libmysql/CMakeLists.txt to see how the .def file is generated for Windows. The corresponding code normally looks like: MERGE_LIBRARIES_SHARED(libmysql ${LIBS_TO_MERGE} EXPORTS ${CLIENT_API_FUNCTIONS} ${CLIENT_API_FUNCTIONS_UNDOCUMENTED} COMPONENT SharedLibraries) If that's the case, collect names that get assigned to the CLIENT_API_FUNCTIONS and CLIENT_API_FUNCTIONS_UNDOCUMENTED variables. Extract the auto-generated mysqld_error.h from Fedora's community-mysql-devel package and copy it into mysql/: $ wget https://rpmfind.net/linux/fedora/linux/development/rawhide/Everything/aarch64/os/Packages/c/community-mysql-devel-8.0.15-1.fc30.aarch64.rpm $ rpm2cpio community-mysql-devel-8.0.15-1.fc30.aarch64.rpm | cpio -idv ./usr/include/mysql/mysqld_error.h Deducing the source file set and compilation/linking options can probably be performed by analyzing the root and component-specific CMakeLists.txt files (see libmysql/, zlib/, etc) and .cmake files under the upstream's cmake/ subdirectory. In practice, however, you may also need to refer to cmake-generated flags.make files or, as a last resort, to see the actual compiler and linker command lines in the build log (see ../README-DEV for details).