An error occurred when I was compiling

[stevenk12]

I encountered the following error while compiling the working directory, and I did not make any changes to the source code. May I ask if the author has encountered it before, or if there are any solutions.

/usr/bin/c++ -fPIC -std=c++14  -g -O3 -Wall -O3 -Wall -shared -Wl,-soname,libhkust_pl_ooqp_itf.so -o /home/kang/diffFlat_Planner/devel/lib/libhkust_pl_ooqp_itf.so CMakeFiles/hkust_pl_ooqp_itf.dir/src/common/solver/ooqp_interface.cc.o CMakeFiles/hkust_pl_ooqp_itf.dir/src/common/solver/qp_solver.cc.o  /home/kang/diffFlat_Planner/src/Dftpav/src/Sim/core/common/thirdparty/ooqp/lib/libooqpgensparse.a /home/kang/diffFlat_Planner/src/Dftpav/src/Sim/core/common/thirdparty/ooqp/lib/libooqpsparse.a /home/kang/diffFlat_Planner/src/Dftpav/src/Sim/core/common/thirdparty/ooqp/lib/libooqpgondzio.a /home/kang/diffFlat_Planner/src/Dftpav/src/Sim/core/common/thirdparty/ooqp/lib/libooqpbase.a /home/kang/diffFlat_Planner/src/Dftpav/src/Sim/core/common/thirdparty/ooqp/lib/libma27.a -lblas -lgfortran 
/usr/bin/ld: cannot find -lgfortran
collect2: error: ld returned 1 exit status
Dftpav/src/Sim/core/common/CMakeFiles/hkust_pl_ooqp_itf.dir/build.make:120: recipe for target '/home/kang/diffFlat_Planner/devel/lib/libhkust_pl_ooqp_itf.so' failed
make[2]: *** [/home/kang/diffFlat_Planner/devel/lib/libhkust_pl_ooqp_itf.so] Error 1
CMakeFiles/Makefile2:2636: recipe for target 'Dftpav/src/Sim/core/common/CMakeFiles/hkust_pl_ooqp_itf.dir/all' failed
make[1]: *** [Dftpav/src/Sim/core/common/CMakeFiles/hkust_pl_ooqp_itf.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....