ld returning exit 1 from GCC while compiling extension

[MatthewRalston]

Any additional information I can provide?

>which ruby
ruby 2.1.10p492 (2016-04-01 revision 54464) [x86_64-linux]
> bundle install
...
make[1]: Leaving directory '/home/matt/.rvm/gems/ruby-2.1.10@gemset/gems/bio-samtools-2.5.1/ext/samtools-1.3.1/htslib-1.3.1'
gcc -pthread -rdynamic   -o samtools bam_index.o bam_plcmd.o sam_view.o bam_cat.o bam_md.o bam_reheader.o bam_sort.o bedidx.o kprobaln.o bam_rmdup.o bam_rmdupse.o bam_mate.o bam_stat.o bam_color.o bamtk.o bam2bcf.o bam2bcf_indel.o errmod.o sample.o sam_opts.o cut_target.o phase.o bam2depth.o padding.o bedcov.o
bamshuf.o faidx.o dict.o stats.o stats_isize.o bam_flags.o bam_split.o bam_tview.o bam_tview_curses.o bam_tview_html.o bam_lpileup.o bam_quickcheck.o bam_addrprg.o libbam.a htslib-1.3.1/libhts.a -lcurses -lm -lz -ldl
/usr/bin/ld: bam_tview_curses.o: undefined reference to symbol 'keypad'
/usr/lib/libtinfo.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make: *** [Makefile:138: samtools] Error 1
rake aborted!
Command failed with status (2): [make...]