ARROW-4845: [R] Compiler warnings on Windows MingW64

[romainfrancois]

No description provided.

[romainfrancois]

This did not test on win builder because I supposed we need a new build of libarrow, #4413 followed up on #4316 and introduced some incompatibilities. https://win-builder.r-project.org/KG75rToaX3Qd/

How do we trigger new builds for https://github.com/rwinlib/arrow ? @jeroen @javierluraschi

[codecov-io]

Codecov Report

Merging #4511 into master will decrease coverage by 13.09%.
The diff coverage is 85.71%.

@@             Coverage Diff             @@
##           master    #4511       +/-   ##
===========================================
- Coverage   88.11%   75.01%    -13.1%     
===========================================
  Files         850       54      -796     
  Lines      105774     3114   -102660     
  Branches     1253        0     -1253     
===========================================
- Hits        93203     2336    -90867     
+ Misses      12326      778    -11548     
+ Partials      245        0      -245

Impacted Files	Coverage Δ
r/src/arrowExports.cpp	72.7% <ø> (ø)	⬆️
r/src/recordbatch.cpp	82.69% <85.71%> (+0.51%)	⬆️
python/pyarrow/ipc.pxi
cpp/src/arrow/csv/chunker-test.cc
cpp/src/parquet/column_page.h
cpp/src/parquet/bloom_filter-test.cc
cpp/src/arrow/array/builder_decimal.cc
cpp/src/plasma/client.cc
cpp/src/arrow/io/test-common.h
cpp/src/arrow/util/int-util-test.cc
... and 788 more

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[nealrichardson]

https://issues.apache.org/jira/browse/ARROW-4845 shows lots of warnings that look to be from different lines--are you sure this is the only change needed?

[romainfrancois]

I'm not sure, that's why I tried to trigger a win builder build with devtools::check_win_devel() but it ended with this:

*** arch - i386
"D:/RCompile/recent/R/bin/i386/Rscript.exe" "../tools/winlibs.R" 0.13.0.9000
Error in download.file(sprintf("https://github.com/rwinlib/arrow/archive/v%s.zip",  : 
  cannot open URL 'https://github.com/rwinlib/arrow/archive/v0.13.0.9000.zip'
In addition: Warning message:
In download.file(sprintf("https://github.com/rwinlib/arrow/archive/v%s.zip",  :
  cannot open URL 'https://github.com/rwinlib/arrow/archive/v0.13.0.9000.zip': HTTP status was '404 Not Found'
Execution halted
make: *** [winlibs] Error 1
ERROR: compilation failed for package 'arrow'
* removing 'd:/RCompile/CRANguest/R-devel/lib/arrow'

before it could show me compile errors.

[pitrou]

Looks like the fix would indeed silence the warning, but some comments.

[romainfrancois]

Perhaps we can use -Wall on travis to get some other warnings as well.

[jeroen]

Once libarrow 0.14 is released you can send a PR to https://github.com/r-windows/rtools-packages and https://github.com/r-windows/rtools-backports and we can upload new binaries on rwinlib.

[wesm]

At some point we need to document the source build process on Windows rather than relying on pre-packaged binaries so that we can run it in CI, otherwise we will eventually get slammed with a Windows-only problem post-release

https://issues.apache.org/jira/browse/ARROW-3758

[jeroen]

The build process is documented and automated.

You can either build libarrow locally or send a PR to https://github.com/r-windows/rtools-backports and then download the binaries from appveyor, and build your R package with that.

There is nothing special about rwinlib, it's just a place where we host binaries for (stable) libraries. But you could host them anywhere else.