Argthtjtr

I am working on a project that uses the package plotly in R.
When I tried installing plotly, hexbin (a dependency) would not compile, because it could not find the gfortran .so libraries.
I have already installed gfortran (gcc64-gfortran.x86_64), but the .so files are not installed or discoverable by ld. Here is the relevant part of the log:

$ R

> install.packages("hexbin", repos = "http://cran.rstudio.com/")

Installing package into ‘/home/ec2-user/R/x86_64-redhat-linux-gnu-library/3.4’



...



gcc -m64 -std=gnu99 -shared -L/usr/lib64/R/lib -L/usr/local/lib64 -o hexbin.so hbin.o hcell.o herode.o hsm.o reg.o -lgfortran -lm -lquadmath - L/usr/lib64/R/lib -lR

/usr/bin/ld: cannot find -lgfortran

/usr/bin/ld: cannot find -lquadmath

collect2: error: ld returned 1 exit status

Running ld -lgfortran --verbose gives me this:

...



==================================================

attempt to open /usr/x86_64-amazon-linux/lib64/libgfortran.so failed

attempt to open /usr/x86_64-amazon-linux/lib64/libgfortran.a failed

attempt to open /usr/lib64/libgfortran.so failed

attempt to open /usr/lib64/libgfortran.a failed

attempt to open /usr/local/lib64/libgfortran.so failed

attempt to open /usr/local/lib64/libgfortran.a failed

attempt to open /lib64/libgfortran.so failed

attempt to open /lib64/libgfortran.a failed

attempt to open /usr/x86_64-amazon-linux/lib/libgfortran.so failed

attempt to open /usr/x86_64-amazon-linux/lib/libgfortran.a failed

attempt to open /usr/local/lib/libgfortran.so failed

attempt to open /usr/local/lib/libgfortran.a failed

attempt to open /lib/libgfortran.so failed

attempt to open /lib/libgfortran.a failed

attempt to open /usr/lib/libgfortran.so failed 

attempt to open /usr/lib/libgfortran.a failed

ld: cannot find -lgfortran

yum info gcc64-gfortran.x86_64 says that my installation of gfortran is at version 6.4.1 from amzn-main.

I had the same issue with a standard AWS Linux instance.

I had to link both, gfortran and quadmath:

sudo ln -s /usr/lib/gcc/x86_64-amazon-linux/6.4.1/libquadmath.so /usr/lib/libquadmath.so

I found the problem. When I searched for the .so fortran file, I used the find command incorrectly.
I was using find / -file gfortran.so instead of find / -file *gfortran*. I simply linked it with sudo ln -s /usr/lib/gcc/x86_64-amazon-linux/6.4.1/libgfortran.so /usr/lib/libgfortran.so, and now the link is resolved.