Trying to install hugs98-Sep2003 on FreeBSD 4.8 produced the following error: $ ./configure ... checking for function_dlopen... yes checking for function_shl_load... no checking for library_dld... no ... $ cd .. $ make ... env HUGSDIR='../hugsdir' HUGSFLAGS='-W' unix/BuildFFI Compiling ../../hugsdir/libraries/Foreign/C/Error.hs Compiling ../../hugsdir/libraries/Foreign/Marshal/Alloc.hs Compiling ../../hugsdir/libraries/Foreign/Marshal/Utils.hs Compiling ../../hugsdir/libraries/System/Posix/Internals.hs Compiling ../../hugsdir/libraries/Text/Regex/Posix.hs Compiling ../../hugsdir/libraries/Network/BSD.hs Compiling ../../hugsdir/libraries/Network/Socket.hs Compiling ../../hugsdir/libraries/System/Posix/Directory.hs /usr/libexec/elf/ld: cannot find -ldl runhugs: Error occurred ERROR "../../hugsdir/libraries/System/Posix/Directory.hs" - Error while running compilation command 'gcc -g -shared -fPIC -D__HUGS__ "-I../hugsdir/include" "../../hugsdir/libraries/System/Posix/Directory.c" -o "../../hugsdir/libraries/System/Posix/Directory.so" -I../../hugsdir/libraries/System/Posix -I../../hugsdir/libraries -I../../hugsdir/include -I/home/rls/hugs98-Sep2003/fptools/libraries/unix/include -ldl' The problem seems to be caused by the fact that FreeBSD (and possibly other BSD-derived systems) have dlopen() etc. in libc, there is no libdl. configure #defines HAVE_LIBDL to 1 if either dlopen() etc. are found in libc or when linking with -ldl. fptools/libraries/unix/package.conf.in however uses #ifdef HAVE_LIBDL to check whether -ldl should be added to extra_libraries. After manually deleting the #ifdef HAVE_LIBDL , "dl" #endif block from package.conf.in make completed successfully and make LibStatus completed without producing errors. Regards, Reinhard