Hi, As I already feared, someone tried to build mysql-connector-c++ [1] against libmysqlclient 5.6.20-1, which results in the following error: …/driver/mysql_metadata.cpp:1216:74: error: ‘dynamic_cast’ not permitted with -fno-rtti How do I remove that compiler flag from CMake output? I already tried adding -frtti to CXXFLAGS in makepkg.conf, but this didn't change the compiler flags. I also tried to add it as an environment variable to the cmake call in PKGBUILD and add a set(CMAKE_CXX_FLAGS "-frtti") at several places in …/CMakeLists.txt, but to no avail, CMake keeps saying -- MySQL CXXFLAGS: -I/usr/include/mysql -fPIC -pipe -msse4.1 -mmmx -fomit-frame-pointer -fstack-protector-strong --param=ssp-buffer-size=4 -fno-strict-aliasing -DBIG_JOINS=1 -felide-constructors -fno-rtti -g -DNDEBUG And why isn't this a problem when building against libmariadbclient 10.0.14? Regards, Marcel [1] https://aur.archlinux.org/packages/mysql-connector-c%2B%2B/