Implement read, write, open, close in the runtime library and LLVM
Currently these can be parsed up to the ASR level:
$ lfortran --show-asr integration_tests/intrinsics_open_close_read_write.f90 --indent
But still have to be implemented in the runtime library and hooked it in the LLVM backend. Or alternatively write an ASR pass that transforms the open
, write
, ..., statements into our Fortran runtime library calls.
First reported in: https://fortran-lang.discourse.group/t/lfortran-exception-visit-read-not-implemented-error/1803