Bug: read() gives invalid output

[kmr-srbh]

This bug was caught when working on #4011.

b.f90

program main
    character :: c
    open(11, file="intrinsics_60_data.txt", form="formatted", access="stream", status="old")
    read(11, *) c
    print *, c
    print*, len(c)
end

$ gfortran b.f90 && ./a.out
 H
           1
$ lfortran b.f90 --no-warnings
Hello
5

intrinsics_60_data.txt

Hello

When ready with a fix, please also verify the integration test intrinsics_60.f90.

[gxyd]

Seems like _lfortran_read_char doesn't take into account the length of the passes character string to it. Probably needs another argument for it. The same issue currently happens for when the input is taken from the console:

program main
    character(len=2) :: c
    read *, c
    print *, c
    print*, len(c)
end

if we enter "apple" as the string from console. It will output:

apple
5

instead of the correct output:

ap
2

Same issue happens for when, padding of spaces needs to be done.

[kmr-srbh]

@gxyd thanks for the finding! This should be easy to fix I think. 👍

[kmr-srbh]

@gxyd are you working on this? I have a fix ready for this.

[gxyd]

I was going to submit a fix just now, but I'm happy to work on this together so that either of our solution can be merged. So, submit a PR for it, and I'll review that.