174964

Ports configured to use Lua (e.g., Wireshark) will throw an error during "make config" about being unable to link against liblua.  Upon review of the port's "config.log" file, one will see linker error messages similar to the following:

configure:25468: checking for luaL_register in -llua
configure:25493: cc -o conftest -O2 -pipe -funit-at-a-time -fno-strict-aliasing -Wall -W -Wextra -Wdeclaration-after-statement -Wendif-labels -Wpointer-arith -Wno-pointer-sign -Wcast-align -Wformat-security -Wold-style-definition -I/usr/local/include/gtk-2.0 -I/usr/local/include/gio-unix-2.0/ -I/usr/local/include/atk-1.0 -I/usr/local/include/cairo -I/usr/local/include/pixman-1 -I/usr/local/include/drm -D_THREAD_SAFE -I/usr/local/include/gdk-pixbuf-2.0 -I/usr/local/include/libpng15 -I/usr/local/include/pango-1.0 -D_REENTRANT -I/usr/local/include/glib-2.0 -I/usr/local/include/freetype2 -I/usr/local/include   -DG_DISABLE_DEPRECATED -DG_DISABLE_SINGLE_INCLUDES -DGSEAL_ENABLE -DGTK_DISABLE_DEPRECATED -DGTK_DISABLE_SINGLE_INCLUDES -D_FORTIFY_SOURCE=2 -D_U_="__attribute__((unused))"  -I/usr/local/include -I/usr/local/include -I/usr/include/pcap -I/usr/local/include/lua51  -L/usr/local/lib -Wl,-rpath=/usr/local/lib -Wl,--as-needed -L/usr/local/lib -L/usr/local/lib -L/usr/local/lib conftest.c
  -llua  -lz  -pthread -pthread -L/usr/local/lib/lua51 -llua -lm  -lm >&5
conftest.c: In function 'main':
conftest.c:65: warning: old-style function definition
/usr/local/lib/lua51/liblua.so: undefined reference to `floor'
/usr/local/lib/lua51/liblua.so: undefined reference to `ceil'
/usr/local/lib/lua51/liblua.so: undefined reference to `cosh'
/usr/local/lib/lua51/liblua.so: undefined reference to `tan'
/usr/local/lib/lua51/liblua.so: undefined reference to `tanh'
/usr/local/lib/lua51/liblua.so: undefined reference to `asin'
/usr/local/lib/lua51/liblua.so: undefined reference to `log'
/usr/local/lib/lua51/liblua.so: undefined reference to `atan'
/usr/local/lib/lua51/liblua.so: undefined reference to `sinh'
/usr/local/lib/lua51/liblua.so: undefined reference to `fmod'
/usr/local/lib/lua51/liblua.so: undefined reference to `acos'
/usr/local/lib/lua51/liblua.so: undefined reference to `exp'
/usr/local/lib/lua51/liblua.so: undefined reference to `sin'
/usr/local/lib/lua51/liblua.so: undefined reference to `pow'
/usr/local/lib/lua51/liblua.so: undefined reference to `atan2'
/usr/local/lib/lua51/liblua.so: undefined reference to `cos'
/usr/local/lib/lua51/liblua.so: undefined reference to `log10'

This happens even though the configuration test program is being linked against libm (as shown in the arguments to the "cc" command above).  Liblua itself is not linked against libm, only libc:

cinep001bsdgw# ldd /usr/local/lib/lua51/liblua-5.1.so.1
lua51/liblua-5.1.so.1:
        libc.so.7 => /lib/libc.so.7 (0x80084a000)

Fix: 

Force the lang/lua port to link against libm by setting LDFLAGS.  For example:

portmaster -m LDFLAGS="-lm" lang/lua
How-To-Repeat: cd /usr/ports/lang/lua; make install
mkdir -p /var/db/ports/wireshark
echo "OPTIONS_FILE_SET+=LUA" > /var/db/ports/wireshark/options
cd /usr/ports/net/wireshark; make config BATCH=yes