[R-SIG-Mac] gfortran: command not found

[Spencer Graves]

Dear Prof. Ripley et al.:


On 7/8/23 1:16 AM, Prof Brian Ripley wrote:
> On 08/07/2023 00:41, Spencer Graves wrote:
>> Hello, Simon Urbanek and Professor Ripley:
>>
>>
>> On 7/7/23 4:21 AM, Simon Urbanek wrote:
>>>
>>>
>>>> On Jul 7, 2023, at 6:54 PM, Prof Brian Ripley 
>>>> <ripley using stats.ox.ac.uk> wrote:
>>>>
>>>> An alternative is not to have gfortran on the path and use a 
>>>> personal Makevars file, as documented at 
>>>> https://cran.r-project.org/doc/manuals/r-devel/R-admin.html#macOS-packages .
>>>>
>>>> Reasons to do it that way include
>>>>
>>>> a) GCC builds have included other compilers including gcc in the 
>>>> same directory as gfortran, and I have been caught in the past by 
>>>> badly-written software looking for gcc as a C compiler and finding 
>>>> that one rather than Apple's gcc which is a wrapper for clang.  (The 
>>>> current gfortran distribution only includes 
>>>> x86_64-apple-darwin20.0-gcc and similar.)
>>>>
>>>> b) If the gfortran you have installed differs from that used to 
>>>> build R, you may need to set FLIBS, and this has happened as 
>>>> different CRAN distributions have been built with different versions 
>>>> of gfortran.
>>>>
>>>> When I do want gfortran on the path, for example to build other 
>>>> software, I do symlink it to somewhere on my path.
>>>>
>>>> I would prefer if Simon continues to give the full path as FC in 
>>>> etc/Makeconf: anyone who wants a different compiler can use a 
>>>> personal Makevars.  (Continues at least for arm64, and I would 
>>>> prefer consistency.)
>>>>
>>>
>>>
>>> I agree - it wasn't entirely intentional (it's really historical), 
>>> but then there was request for a PATH-less gfortran settings. After 
>>> this discussion I agree that it's not a good idea since the 
>>> instructions on CRAN should be fully self-sufficient *and* we want to 
>>> avoid other incompatible Fortran compilers. (I have trouble reaching 
>>> the x86_64 build machine from home right now, so I'll change it on 
>>> Monday).
>>
>>
>>        Might it be feasible and appropriate for me to try to do this 
>> on my 2014 MacBook Pro running macOS 11.7.8?
>>
>>
>>        I ask, because I have so far not been able to parse the 
>> instructions in the link Prof. Ripley provided above.  I found a ".r" 
>> subdirectory in my default directory, but its contents seems to be 
>> only "crashpad_database".  I did not see anything that looked to me 
>> like, "HOME/.R/Makevars-R_PLATFORM".  ???
> 
> You need to create the file (which is called ~/.R/Makevars in the 
> section I referred you to).   Using a case-insenstive file system does 
> not help (I had no idea what created ~/.r/crashpad_database, but 
> Googling suggests RStudio).
> 
> (If you did not have ~/.r, you would need mkdir ~/.R in a Terminal.)
> Then use your favourite editor to create a file ~/.r/Makevars containing 
> the single line
> 
> FC=/opt/gfortran/bin/gfortran
> 
> 
> The only issue is if you ever install a new gfortran you will need to 
> edit/remove this file -- it is easily forgotten.  As Simon says he is 
> changing this soon, I would make a note to remove the file when you 
> update R.


	  For now, I've added a file "~/.r/Makevars" containing this single 
line and deleted the corresponding reference from "/etc/paths".  I 
rebooted and confirmed that it works.  Thanks very much.  Spencer Graves
>