[R-pkg-devel] what is difference between Mac setup of rhub and CRAN

See answers inline.

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The package has C++ code which relies on clang-3.3 or newer and relies on -pthread. It has in it's src/Makevars (https://github.com/bnosac/ruimtehol/blob/master/src/Makevars)

PKG_LIBS = -pthread
PKG_CPPFLAGS = -pthread

Is that what you mean with linking to a system library?

Possibly, yes.

What version of the compiler is running on rhub and how is it different from CRAN r-release-osx-x86_64 or even CRAN r-oldrel-osx-x86_64

R-hub uses the standard system compiler in Xcode. CRAN checks use
their custom built clang compiler. This is usually compatible with the
system compiler, except for some rare ABI issues. You can download it
at https://cran.r-project.org/bin/macosx/tools/  The check flavors
page at https://cran.r-project.org/web/checks/check_flavors.html might
be outdated, as it still shows clang 4.0.0. I don't know, I cannot
speak for CRAN.

About CRAN (Question 2): What can be a reason why a package fails on r-release-osx-x86_64 but checked fine on r-oldrel-osx-x86_64

Hard to say. I think you only have a real chance to fix this if you
can reproduce it on your machine.

Gabor

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