[R-SIG-Mac] "cannot run mixed C/Fortran code"

[Duncan Murdoch]

I found the problem.  /usr/local/lib had old copies of libgfortran* and 
libquadmath* from 2015, and removing these allowed things to proceed. 
The current copies are in /usr/local/gfortran/lib.

That directory contains a lot of old junk; I'll probably find more needs 
to go too.

Duncan Murdoch

On 04/08/2020 9:58 a.m., Duncan Murdoch wrote:
> After updating to Catalina, I've installed the Xcode command line tools
> version 11.4.1, and gfortran 8.2.  When trying to build R, configure dies:
> 
>    checking whether gfortran appends underscores to external names... yes
>    checking whether gfortran appends extra underscores to external
> names... no
>    checking whether mixed C/Fortran code can be run... configure:
> WARNING: cannot run mixed C/Fortran code
>    configure: error: Maybe check LDFLAGS for paths to Fortran libraries?
> 
> I don't have LDFLAGS set.  I'm not certain I'm running the right
> compilers (I might have old ones that have precedence on the path).  Are
> these the versions I should be seeing?
> 
> $ clang --version
> Apple clang version 11.0.3 (clang-1103.0.32.59)
> Target: x86_64-apple-darwin19.6.0
> Thread model: posix
> InstalledDir: /Library/Developer/CommandLineTools/usr/bin
> 
> $ gfortran --version
> GNU Fortran (GCC) 8.2.0
> Copyright (C) 2018 Free Software Foundation, Inc.
> This is free software; see the source for copying conditions.  There is NO
> warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
> 
> If those are the right versions, any other suggestions on how to fix the
> configure problem?
> 
> Duncan Murdoch
>