Build fails with clang 4.0.0 on FreeBSD 11.1

[yarwelp]

Similar issue to #97 - compiler warnings stop build.

./buildrump.sh

[...]

/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:1948:16: error: taking address of packed member 'l_ad' of class or structure 'file_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
                l_ad_p    = &fe->l_ad;
                             ^~~~~~~~
/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:1949:20: error: taking address of packed member 'logblks_rec' of class or structure 'file_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
--- dependall-libumap ---
--- umap_vnops.pico ---
--- dependall-libudf ---
                logblks_rec_p = &fe->logblks_rec;
                                 ^~~~~~~~~~~~~~~
/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:1956:16: error: taking address of packed member 'l_ad' of class or structure 'extfile_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
--- dependall-libumap ---
#   compile  libumap/umap_vnops.pico
--- dependall-libudf ---
                l_ad_p    = &efe->l_ad;
--- dependall-libumap ---
/usr/home/yarwelp/br/obj/tooldir/bin/x86_64--netbsd-clang -O2 -g  -ffreestanding -fno-strict-aliasing -mno-red-zone -mno-mmx -mno-sse -mno-avx -msoft-float  -std=gnu99     -Wno-sign-compare -Wno-pointer-sign  -Wall -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Wno-sign-compare  -Wa,--fatal-warnings -Wreturn-type -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -Wextra -Wno-unused-parameter -Wno-sign-compare -Werror -Wno-format-zero-length -Wno-pointer-sign -Wno-conversion    -DRUMPUSER_CONFIG=yes -I/usr/home/yarwelp/br/obj/tooldir/autoconf -I/usr/home/yarwelp/br/obj/tooldir/compat/include -I/usr/home/yarwelp/br/obj/dest.stage/usr/include  -DCOMPAT_50 -DCOMPAT_60 -DCOMPAT_70 -nostdinc -imacros /usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../include/opt/opt_rumpkernel.h -imacros /usr/home/yarwelp/br/obj/tooldir/include/opt_buildrump.h -I/usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap -I. -I/usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../../../common/include -I/usr/home/yarwelp/br/src/sys/rump/fs/lib--- dependall-libudf ---
                             ^~~~~~~~~
--- dependall-libumap ---
/libumap/../../../include -I/usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../include/opt -I/usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../../arch -I/usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../.. -DRUMP_USE_CTOR -DRUMP_CURLWP=RUMP_CURLWP___THREAD -DDIAGNOSTIC -DKTRACE -U__FreeBSD__  -c    -fPIC -g /usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap/../../../../miscfs/umapfs/umap_vnops.c -o umap_vnops.pico
--- dependall-libudf ---
/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:1957:20: error: taking address of packed member 'logblks_rec' of class or structure 'extfile_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
                logblks_rec_p = &efe->logblks_rec;
                                 ^~~~~~~~~~~~~~~~
/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:2015:13: error: taking address of packed member 'l_ad' of class or structure 'alloc_ext_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
                l_ad_p = &ext->l_ad;
                          ^~~~~~~~~
/usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf/../../../../fs/udf/udf_allocation.c:2121:13: error: taking address of packed member 'l_ad' of class or structure 'alloc_ext_entry' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
                l_ad_p = &ext->l_ad;
--- dependall-libtmpfs ---
A failure has been detected in another branch of the parallel make
--- dependall-libudf ---
                          ^~~~~~~~~
6 errors generated.
*** [udf_allocation.pico] Error code 1
--- dependall-libtmpfs ---
nbmake[4]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libtmpfs
*** [dependall] Error code 2
--- dependall-libudf ---
nbmake[4]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf
1 error
--- dependall-libtmpfs ---
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libtmpfs
--- dependall-libudf ---
nbmake[4]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf
--- dependall-libtmpfs ---
1 error
--- dependall-libudf ---
*** [dependall] Error code 2
--- dependall-libumap ---
A failure has been detected in another branch of the parallel make
--- dependall-libtmpfs ---
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libtmpfs
--- dependall-libudf ---
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf
--- dependall-libumap ---
nbmake[4]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap
--- dependall-libtmpfs ---
*** [dependall-libtmpfs] Error code 2
nbmake[2]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib
--- dependall-libumap ---
*** [dependall] Error code 2
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap
--- dependall-libudf ---
1 error
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libudf
*** [dependall-libudf] Error code 2
nbmake[2]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib
--- dependall-libumap ---
1 error
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libumap
*** [dependall-libumap] Error code 2
nbmake[2]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib
--- dependall-libunion ---
A failure has been detected in another branch of the parallel make
nbmake[4]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libunion
*** [dependall] Error code 2
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libunion
1 error
nbmake[3]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib/libunion
*** [dependall-libunion] Error code 2
nbmake[2]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib
4 errors
nbmake[2]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs/lib
*** [dependall-lib] Error code 2

nbmake[1]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs
1 error

nbmake[1]: stopped in /usr/home/yarwelp/br/src/sys/rump/fs
*** [dependall-/usr/home/yarwelp/br/src/sys/rump/fs] Error code 2

nbmake: stopped in /usr/home/yarwelp/br/src
1 error

nbmake: stopped in /usr/home/yarwelp/br/src
>> ERROR:
>> make /usr/home/yarwelp/br/obj/Makefile.third dependall