Description: ------------ See also http://bugs.mysql.com/bug.php?id=37347 gcc by default adds library init and shutdown functions _init() and _fini() to shared libraries it produces which are called by dlopen() and dlclose() replacing a UDF shared library and then dropping the last registered function from it will usually cause the server to crash in the dlclose() call as it swaps in a so far unused library page that is supposed to hold _fini() which is now already at some other place in the library file, and so invalid code is called gcc can be told to not include these init/deinit functions with the -nostartfiles option in the linker stage, some extra magic is needed to make libtool accept the option as it doesn't seem to have direct support for this problem though is that the required extra LDFLAGS in Makefile.am are gcc specific and likely to break builds with other compilers ...