How to specify an extra lib during a port build?

[Yuri]

While attempting to port one Haskell package, I got this failure:

|Configuring library for hmatrix-0.20.0.0.. cabal: Missing dependency on 
a foreign library: * Missing (or bad) C library: gfortran This problem 
can usually be solved by installing the system package that provides 
this library (you may need the "-dev" version). If the library is 
already installed but in a non-standard location then you can use the 
flags --extra-include-dirs= and --extra-lib-dirs= to specify where it 
is.If the library file does exist, it may contain errors that are caught 
by the C compiler at the preprocessing stage. In this case you can 
re-run configure with the verbosity flag -v3 to see the error messages. 
libgfortran.so is in /usr/local/lib/gcc9. It seems like ||--extra-lib-dirs=|  is a configure flag for ghc.

What is a proper way to resolve this?


Thanks,
Yuri

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