[R-sig-Debian] Ubuntu 16.10 Yakkety Yak uses GCC 6 but -std=c++98 is missing

[Kirill Müller]

Thanks. I have now CXX = g++ -std=c++98 in my /etc/R/Makeconf, it's 
picked up properly. I can only assume that the last -std= option wins if 
more than one are given on the same command line [1].


-Kirill


[1] http://stackoverflow.com/q/40563269/946850



On 12.11.2016 03:01, Dirk Eddelbuettel wrote:
> On 11 November 2016 at 23:48, Kirill Müller wrote:
> | After upgrading to Ubuntu 16.10, which brings GCC 6, I've noticed that
> | packages are compiled in C++14 mode by default. Here's what a g++
> | command for compiling one of Rcpp's modules look like on my system:
> |
> | g++ -I/usr/share/R/include -DNDEBUG -I../inst/include/     -fpic  -g -O2
> | -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time
> | -D_FORTIFY_SOURCE=2 -g  -c barrier.cpp -o barrier.o
> |
> | According to GCC news [1], the default is now C++14 if no -std is given.
> | R-admin suggests adapting the configuration for GCC 6 [2].
> |
> | I'm using r-base-core in version 3.3.2-1xenial0 from the Ubuntu repo
> | [3]. Please advise.
>
> Hm. We had g++-6.* (which does indeed default to C++14) in Debian unstable
> for a while now, without problems.
>
> This issue _may_ be fixable by rebuilding r-base-core, but then it would have
> been needed for Debian too. Not sure.
>
> This may be an Ubuntu-lagging-Debian issue because we may be rebuilding more
> consistently in Debian whereas Ubuntu thinks that R is built with gcc-5 (as
> it was) but is now used with gcc-6. Ooops.
>
> You _could_ try idea this by editing /etc/R/Makeconf and inserting the
> missing -std=c++-98 for the default CXX builds.
>
> I am still on 16.04 with my machines as I had too much other stuff going on.
> Please try a test or two at your end and report back. We should be able to
> get this squared.
>
> Dirk
>