This unfortunately does not compile on OS X (tested on El Capitan).

Perhaps instead we need to guard this in https://github.com/RcppCore/Rcpp/blob/master/inst/include/Rcpp/platform/compiler.h, with something like

#define RCPP_DEMANGLING_SUPPORT
#ifdef __ALPINE // a better way of detecting 'just alpine'?
# undef RCPP_DEMANGLING_SUPPORT
#endif

and then guard based on that?

It failed because another change is missed. No __GLIBC__ is defined on OSX. See thirdwing@8db55e0

@kevinushey From the FAQ (http://wiki.musl-libc.org/wiki/FAQ#Q:_why_is_there_no_MUSL_macro_.3F), it seems no way to detect usage of musl.

We could put a else-if in there and have the Alpine user (at least for now) define that themselves...

@thirdwing but backtraces do currently work on OS X, so there must be a more scoped / targeted change. I loathe the idea of making a configure script to do it, though.

@kevinushey Yes, OSX doesn't define __GLIBC__ and it does have execinfo.h.

The only idea I have now is to detect execinfo.h in the makefile and add something like -DHAVE_EXECINFO into PKG_CPPFLAGS.

As I said before, add a test for __ALPINE here and have the Alpine folks add -D__ALPINE=1 to their PKG_CXXFLAGS. This will work for now until they do us the pleasure of defining something in Musl.

I have no intention of breaking OS X, and no appetite for byzantine build mechanisms.

Totally agree.

On Mon, Mar 21, 2016 at 3:04 PM, Dirk Eddelbuettel <notifications@github.com

wrote:

As I said before, add a test for __ALPINE here
https://github.com/RcppCore/Rcpp/blob/0.12.3/src/api.cpp#L37 and have
the Alpine folks add -D__ALPINE=1 to their PKG_CXXFLAGS. This will work
for now until they do us the pleasure of defining something in Musl.

I have no intention of breaking OS X, and no appetite for byzantine build
mechanisms.

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#449 (comment)

Qiang Kou
qkou@umail.iu.edu
School of Informatics and Computing, Indiana University

As I said before, add a test for __ALPINE here and have the Alpine folks add -D__ALPINE=1 to their PKG_CXXFLAGS. This will work for now until they do us the pleasure of defining something in Musl.

I have no intention of breaking OS X, and no appetite for byzantine build mechanisms

I have added a __MUSL__ test instead of __ALPINE as the issue is directly related with the musl glib and more linux distributions make use of it, not just Alpine.

That looks much better. And I presume it works for you, ie __MUSL__ is in fact defined?

(And please don't get me wrong -- I have nothing against Musl or Alpine. I use Docker quite a bit and have quite some sympathy for thinner builds but we got to this right and not break a bazillion existing use cases ...)

That looks much better. And I presume it works for you, ie MUSL is in fact defined?

Yes!

For testing purposes (and given I'm using docker) I have added the -D__MUSL__ to the R compilation options (PKG_CXXFLAGS):

x86_64-alpine-linux-musl-g++ -I/usr/lib/R/include -DNDEBUG -D__MUSL__ -I../inst/include -DCOMPILING_DPLYR -Os -fomit-frame-pointer -I"/app/packrat/lib/x86_64-alpine-linux-musl/3.2
.3/Rcpp/include" -I"/app/packrat/lib/x86_64-alpine-linux-musl/3.2.3/BH/include"   -fpic  -Os -fomit-frame-pointer  -c RcppExports.cpp -o RcppExports.o

but once Alpine adds that to the PKG_CXXFLAGS it should work out of the box 👍

Err, yes, I understand the PKG_CXXFLAGS trick; after all it was me who suggested it to you 😉

But what is missing here is someone checking with the good folks of the Musl library to please add such an unmistakable identifier as we cannot possibly do this piecemeal package by package.

So let me rephrase: Can you please run a recursive grep over the C library headers for Musl and check that __MUSL__ is there?

But what is missing here is someone checking with the good folks of the Musl library to please add such an unmistakable identifier as we cannot possibly do this piecemeal package by package.

So let me rephrase: Can you please run a recursive grep over the C library headers for Musl and check that MUSL is there?

Here's the list of macros: https://gist.github.com/lostie/2b60cb4afb3bbba0b928

__MUSL__ is not present as stated in their F.A.Q.

All I can do is request MUSL community (I've already sent them an e-mail) to set by default in their library.

Yes, please liaise with them. They will need this.

I'll fold this in now. We have Rcpp 0.12.4 pending at CRAN so with be for the next release anyway.