Error while emerging arpack

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild  N     ] sci-libs/arpack-3.1.5  USE="-doc -examples -mpi"
[ebuild  N     ] sci-mathematics/octave-4.2.2  USE="X glpk gnuplot gui imagemagick opengl qhull qrupdate readline sparse zlib -curl -doc -fftw -graphicsmagick -hdf5 -java -openssl -portaudio -postscript -sndfile -static-libs"

Would you like to merge these packages? [Yes/No] y

>>> Verifying ebuild manifests

>>> Emerging (1 of 2) sci-libs/arpack-3.1.5::gentoo
 * Fetching files in the background.
 * To view fetch progress, run in another terminal:
 * tail -f /var/log/emerge-fetch.log
 * arpack-ng_3.1.5.tar.gz BLAKE2B SHA512 size ;-) ...                    [ ok ]
 * Using following Fortran compiler:
 *   F77: x86_64-pc-linux-gnu-gfortran
 *   FC:  x86_64-pc-linux-gnu-gfortran
>>> Unpacking source...
>>> Unpacking arpack-ng_3.1.5.tar.gz to /var/tmp/portage/sci-libs/arpack-3.1.5/work
>>> Source unpacked in /var/tmp/portage/sci-libs/arpack-3.1.5/work
>>> Preparing source in /var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-ng-3.1.5 ...
 * Running elibtoolize in: arpack-ng-3.1.5/
 *   Applying portage/1.2.0 patch ...
 *   Applying sed/1.5.6 patch ...
 *   Applying as-needed/2.4.2 patch ...
 *   Applying target-nm/2.4.2 patch ...
 *   Applying ppc64le/2.4.2 patch ...
>>> Source prepared.
>>> Configuring source in /var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-ng-3.1.5 ...
Package lapack was not found in the pkg-config search path.
Perhaps you should add the directory containing `lapack.pc'
to the PKG_CONFIG_PATH environment variable
Package 'lapack', required by 'virtual:world', not found
>>> Working in BUILD_DIR: "/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-3.1.5_build"
 * econf: updating arpack-ng-3.1.5/config.guess with /usr/share/gnuconfig/config.guess
 * econf: updating arpack-ng-3.1.5/config.sub with /usr/share/gnuconfig/config.sub
/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-ng-3.1.5/configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --disable-dependency-tracking --disable-silent-rules --libdir=/usr/lib64 --docdir=/usr/share/doc/arpack-3.1.5 --disable-static --with-blas=-L/usr/lib64/blas/reference -lblas  --with-lapack= --disable-mpi
checking for a BSD-compatible install... /usr/lib/portage/python3.6/ebuild-helpers/xattr/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking for x86_64-pc-linux-gnu-g77... x86_64-pc-linux-gnu-gfortran
checking whether the Fortran 77 compiler works... yes
checking for Fortran 77 compiler default output file name... a.out
checking for suffix of executables...
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU Fortran 77 compiler... yes
checking whether x86_64-pc-linux-gnu-gfortran accepts -g... yes
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
checking how to print strings... printf
checking for style of include used by make... GNU
checking for x86_64-pc-linux-gnu-gcc... x86_64-pc-linux-gnu-gcc
checking whether we are using the GNU C compiler... yes
checking whether x86_64-pc-linux-gnu-gcc accepts -g... yes
checking for x86_64-pc-linux-gnu-gcc option to accept ISO C89... none needed
checking whether x86_64-pc-linux-gnu-gcc understands -c and -o together... yes
checking dependency style of x86_64-pc-linux-gnu-gcc... none
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for fgrep... /bin/grep -F
checking for ld used by x86_64-pc-linux-gnu-gcc... /usr/x86_64-pc-linux-gnu/bin/ld
checking if the linker (/usr/x86_64-pc-linux-gnu/bin/ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/x86_64-pc-linux-gnu-nm -B
checking the name lister (/usr/bin/x86_64-pc-linux-gnu-nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking whether the shell understands some XSI constructs... yes
checking whether the shell understands "+="... yes
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/x86_64-pc-linux-gnu/bin/ld option to reload object files... -r
checking for x86_64-pc-linux-gnu-objdump... x86_64-pc-linux-gnu-objdump
checking how to recognize dependent libraries... pass_all
checking for x86_64-pc-linux-gnu-dlltool... no
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for x86_64-pc-linux-gnu-ar... x86_64-pc-linux-gnu-ar
checking for archiver @FILE support... @
checking for x86_64-pc-linux-gnu-strip... x86_64-pc-linux-gnu-strip
checking for x86_64-pc-linux-gnu-ranlib... x86_64-pc-linux-gnu-ranlib
checking command to parse /usr/bin/x86_64-pc-linux-gnu-nm -B output from x86_64-pc-linux-gnu-gcc object... ok
checking for sysroot... no
checking for x86_64-pc-linux-gnu-mt... no
checking for mt... no
checking if : is a manifest tool... no
checking how to run the C preprocessor... x86_64-pc-linux-gnu-gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if x86_64-pc-linux-gnu-gcc supports -fno-rtti -fno-exceptions... no
checking for x86_64-pc-linux-gnu-gcc option to produce PIC... -fPIC -DPIC
checking if x86_64-pc-linux-gnu-gcc PIC flag -fPIC -DPIC works... yes
checking if x86_64-pc-linux-gnu-gcc static flag -static works... yes
checking if x86_64-pc-linux-gnu-gcc supports -c -o file.o... yes
checking if x86_64-pc-linux-gnu-gcc supports -c -o file.o... (cached) yes
checking whether the x86_64-pc-linux-gnu-gcc linker (/usr/x86_64-pc-linux-gnu/bin/ld -m elf_x86_64) supports shared libraries... yes
checking whether -lc should be explicitly linked in... no
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... no
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... no
checking for x86_64-pc-linux-gnu-gfortran option to produce PIC... -fPIC
checking if x86_64-pc-linux-gnu-gfortran PIC flag -fPIC works... yes
checking if x86_64-pc-linux-gnu-gfortran static flag -static works... yes
checking if x86_64-pc-linux-gnu-gfortran supports -c -o file.o... yes
checking if x86_64-pc-linux-gnu-gfortran supports -c -o file.o... (cached) yes
checking whether the x86_64-pc-linux-gnu-gfortran linker (/usr/x86_64-pc-linux-gnu/bin/ld -m elf_x86_64) supports shared libraries... yes
checking dynamic linker characteristics... (cached) GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking how to get verbose linking output from x86_64-pc-linux-gnu-gfortran... -v
checking for Fortran 77 libraries of x86_64-pc-linux-gnu-gfortran...  -L/usr/lib/gcc/x86_64-pc-linux-gnu/8.3.0 -L/usr/lib/gcc/x86_64-pc-linux-gnu/8.3.0/../../../../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L/usr/lib/gcc/x86_64-pc-linux-gnu/8.3.0/../../../../x86_64-pc-linux-gnu/lib -L/usr/lib/gcc/x86_64-pc-linux-gnu/8.3.0/../../.. -lgfortran -lm -lquadmath
checking for dummy main to link with Fortran 77 libraries... none
checking for Fortran 77 name-mangling scheme... lower case, underscore, no extra underscore
checking for sgemm_ in -L/usr/lib64/blas/reference -lblas ... yes
checking for cheev_... no
checking for cheev_ in -llapack... no
checking for cheev_ in -llapack_rs6k... no
configure: error: Cannot find LAPACK libraries

!!! Please attach the following file when seeking support:
!!! /var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-3.1.5_build/config.log
 * ERROR: sci-libs/arpack-3.1.5::gentoo failed (configure phase):
 *   econf failed
 *
 * Call stack:
 *               ebuild.sh, line  125:  Called src_configure
 *             environment, line 2816:  Called autotools-utils_src_configure
 *             environment, line  751:  Called econf '--docdir=/usr/share/doc/arpack-3.1.5' '--disable-static' '--with-blas=-L/usr/lib64/blas/reference -lblas ' '--with-lapack=' '--disable-mpi'
 *        phase-helpers.sh, line  681:  Called __helpers_die 'econf failed'
 *   isolated-functions.sh, line  112:  Called die
 * The specific snippet of code:
 *   		die "$@"
 *
 * If you need support, post the output of `emerge --info '=sci-libs/arpack-3.1.5::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=sci-libs/arpack-3.1.5::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/sci-libs/arpack-3.1.5/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/sci-libs/arpack-3.1.5/temp/environment'.
 * Working directory: '/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-3.1.5_build'
 * S: '/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-ng-3.1.5'

>>> Failed to emerge sci-libs/arpack-3.1.5, Log file:

>>>  '/var/tmp/portage/sci-libs/arpack-3.1.5/temp/build.log'

 * Messages for package sci-libs/arpack-3.1.5:

 * ERROR: sci-libs/arpack-3.1.5::gentoo failed (configure phase):
 *   econf failed
 *
 * Call stack:
 *               ebuild.sh, line  125:  Called src_configure
 *             environment, line 2816:  Called autotools-utils_src_configure
 *             environment, line  751:  Called econf '--docdir=/usr/share/doc/arpack-3.1.5' '--disable-static' '--with-blas=-L/usr/lib64/blas/reference -lblas ' '--with-lapack=' '--disable-mpi'
 *        phase-helpers.sh, line  681:  Called __helpers_die 'econf failed'
 *   isolated-functions.sh, line  112:  Called die
 * The specific snippet of code:
 *   		die "$@"
 *
 * If you need support, post the output of `emerge --info '=sci-libs/arpack-3.1.5::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=sci-libs/arpack-3.1.5::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/sci-libs/arpack-3.1.5/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/sci-libs/arpack-3.1.5/temp/environment'.
 * Working directory: '/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-3.1.5_build'
 * S: '/var/tmp/portage/sci-libs/arpack-3.1.5/work/arpack-ng-3.1.5'