Issue linking in CRAN M1 server

[david-cortes]

I'm having issues with the CRAN checks on apple M1 for a package that links to float:
https://www.stats.ox.ac.uk/pub/bdr/M1mac/recometrics.log
https://www.stats.ox.ac.uk/pub/bdr/M1mac/recometrics.out

Seems the linking is not working:

* installing *source* package ‘recometrics’ ...
** package ‘recometrics’ successfully unpacked and MD5 sums checked
** using staged installation
** libs
clang++ -std=gnu++11 -I"/Users/ripley/R/R-devel/include" -DNDEBUG -D_FOR_R -I'/Users/ripley/R/Library/Rcpp/include' -I'/Users/ripley/R/Library/float/include' -I/opt/R/arm64/include   -fPIC  -g -O2  -c RcppExports.cpp -o RcppExports.o
clang++ -std=gnu++11 -I"/Users/ripley/R/R-devel/include" -DNDEBUG -D_FOR_R -I'/Users/ripley/R/Library/Rcpp/include' -I'/Users/ripley/R/Library/float/include' -I/opt/R/arm64/include   -fPIC  -g -O2  -c Rwrapper.cpp -o Rwrapper.o
clang++ -std=gnu++11 -dynamiclib -Wl,-headerpad_max_install_names -undefined dynamic_lookup -single_module -multiply_defined suppress -L/Users/ripley/R/R-devel/lib -L/opt/R/arm64/lib -o recometrics.so RcppExports.o Rwrapper.o -L/Users/ripley/R/R-devel/lib -lRblas -L/opt/R/arm64/gfortran/lib/gcc/aarch64-apple-darwin20.2.0/11.0.0 -L/opt/R/arm64/gfortran/lib -lgfortran -lemutls_w -lm -L/Users/ripley/R/Library/float/libs /Users/ripley/R/Library/float/libs/float.so -Wl,-rpath /Users/ripley/R/Library/float/libs -L/Users/ripley/R/R-devel/lib -lR -Wl,-framework -Wl,CoreFoundation
installing to /Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00LOCK-recometrics/00new/recometrics/libs
** R
** inst
** byte-compile and prepare package for lazy loading
** help
*** installing help indices
** building package indices
** installing vignettes
** testing if installed package can be loaded from temporary location
Error: package or namespace load failed for ‘recometrics’ in dyn.load(file, DLLpath = DLLpath, ...):
 unable to load shared object '/Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00LOCK-recometrics/00new/recometrics/libs/recometrics.so':
  dlopen(/Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00LOCK-recometrics/00new/recometrics/libs/recometrics.so, 6): Library not loaded: float.so
  Referenced from: /Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00LOCK-recometrics/00new/recometrics/libs/recometrics.so
  Reason: image not found
Error: loading failed
Execution halted
ERROR: loading failed
* removing ‘/Users/ripley/R/packages/tests-devel/recometrics.Rcheck/recometrics’

* using log directory ‘/Users/ripley/R/packages/tests-devel/recometrics.Rcheck’
* using R Under development (unstable) (2021-07-15 r80623)
* using platform: aarch64-apple-darwin20.5.0 (64-bit)
* using session charset: UTF-8
* using option ‘--no-stop-on-test-error’
* checking for file ‘recometrics/DESCRIPTION’ ... OK
* checking extension type ... Package
* this is package ‘recometrics’ version ‘0.1.2’
* checking package namespace information ... OK
* checking package dependencies ... OK
* checking if this is a source package ... OK
* checking if there is a namespace ... OK
* checking for executable files ... OK
* checking for hidden files and directories ... OK
* checking for portable file names ... OK
* checking for sufficient/correct file permissions ... OK
* checking whether package ‘recometrics’ can be installed ... ERROR
Installation failed.
See ‘/Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00install.out’ for details.
* DONE

Status: 1 ERROR
See
  ‘/Users/ripley/R/packages/tests-devel/recometrics.Rcheck/00check.log’
for details.

       12.06 real        10.47 user         1.09 sys

Works fine in other platforms though.

[david-cortes]

From Prof. Ripley:
"At least two issues need to be addressed:

• float.so is not in general a library.
• -Wl,-rpath is not portable and may well not do what it does on Linux.

See 'Writing R Extensions' §5.8 for fairly portable solutions."

In 'Writing R Extensions' it mentions that shared objects in mac should end in .dylib and that .so objects are not linkeable there.

It also mentions that rpath is specific to the GNU linker - should packages that link to float perhaps also have a requirement for GNU linker specified? Not sure if adding a variable LD in Makevars + SystemRequires in DESCRIPTION would do though.

[snoweye]

Try the static library on mac. See rsparse for example.

The mac needs special treatment such as here as LinkingTo may be for simple usage.

[david-cortes]

@snoweye Thanks for the reply. I see nevertheless that the code in that PR is no longer used in the current master branch.Does that mean it is now enough to just use float:::ldflags(static=TRUE) for macOS?