[Rcpp-devel] cxxfunction -- extra argument to g++

[Whit Armstrong]

Still not sure I get it, but here is a portable example:

require(inline)
require(Rcpp)
cppbugs.plugin <- getPlugin("Rcpp")
cppbugs.plugin$env$PKG_CXXFLAGS <- "-std=c++0x"

## this works
foo <- cxxfunction(signature(hat="numeric"), body="return
R_NilValue;",settings=cppbugs.plugin)

## this blows up
foo.bar <- cxxfunction(signature(hat="numeric"), body="#include
<armadillo>\nreturn R_NilValue;",settings=cppbugs.plugin,verbose=TRUE)


-Whit




On Tue, Jan 24, 2012 at 3:36 PM, Whit Armstrong
<armstrong.whit at gmail.com> wrote:
> Thanks, Dirk, as always for the quick response.
>
> It works, but I get an unusual compile error with the most recent
> RcppArmadillo (installed with install.packages this morning).
>
> require(inline)
> require(Rcpp)
> require(RcppArmadillo)
> cppbugs.plugin <- getPlugin("RcppArmadillo")
> cppbugs.plugin$env$PKG_CXXFLAGS <- "-std=c++0x"
> foo <- cxxfunction(signature(hat="numeric"), body="return
> R_NilValue;",settings=cppbugs.plugin)
>
> results in:
>
> Error in compileCode(f, code, language = language, verbose = verbose) :
>  Compilation ERROR, function(s)/method(s) not created! In file
> included from /usr/local/lib/R/site-library/RcppArmadillo/include/armadillo_bits/Mat_meat.hpp:6091:0,
>                 from
> /usr/local/lib/R/site-library/RcppArmadillo/include/armadillo:369,
>                 from
> /usr/local/lib/R/site-library/RcppArmadillo/include/RcppArmadilloForward.h:36,
>                 from
> /usr/local/lib/R/site-library/RcppArmadillo/include/RcppArmadillo.h:25,
>                 from file1724747be803.cpp:3:
> /usr/local/lib/R/site-library/RcppArmadillo/include/RcppArmadillo/Mat_meat.h:
> In function ‘void arma::RcppArmadillo::check()’:
> /usr/local/lib/R/site-library/RcppArmadillo/include/RcppArmadillo/Mat_meat.h:34:5:
> error: expected ‘;’ before ‘}’ token
> make: *** [file1724747be803.o] Error 1
> In addition: Warning message:
> running command '/usr/lib/R/bin/R CMD SHLIB file1724747be803.cpp 2>
> file1724747be803.cpp.err.txt' had status 1
>
>
> Probably something I've overlooked.
>
> However, changing the 'cppbugs.plugin <- getPlugin("RcppArmadillo")'
> command to 'cppbugs.plugin <- getPlugin("Rcpp")' allows the example to
> compile.
>
> Is there a c++0x issue in the latest RcppArmadillo?  I have:
> Version:            0.2.34
> Date:               $Date: 2011-12-12 16:56:37 -0600 (Mon, 12 Dec 2011) $
>
> Anyway, I'll keep tinkering...
>
> -Whit
>
>
>
>
> On Tue, Jan 24, 2012 at 3:18 PM, Dirk Eddelbuettel <edd at debian.org> wrote:
>>
>> On 24 January 2012 at 14:46, Whit Armstrong wrote:
>> | using cxxfunction is there an easy (not using a custom plugin) way to
>> | add -std=c++0x to the g++ call?
>>
>> The best way, I think, is to call a plugin and to modify it.
>>
>> Quick example:
>>
>>
>> R> myplugin <- getPlugin("Rcpp")
>> R> myplugin$env$PKG_CXXFLAGS <- "-std=c++0x"
>> R> f <- cxxfunction(signature(), settings=myplugin, body='
>> +    std::vector<double> x = { 1.0, 2.0, 3.0 };  // fails without -std=c++0x
>> +    return Rcpp::wrap(x);
>> + ')
>> R> f()
>> [1] 1 2 3
>> R>
>>
>>
>> If you don't use the modified settings, it'll blow up as the 'curly init' is
>> a new feature:
>>
>>   filebee52557bd2.cpp:32:44: error: in C++98 ‘x’ must be initialized by constructor, not by ‘{...}’
>>   filebee52557bd2.cpp:32:44: error: could not convert ‘{1.0e+0, 2.0e+0, 3.0e+0}’ from ‘<brace-enclosed initializer list>’ to ‘std::vector<double>’
>>
>> but with the switch it all flies.
>>
>> I think I'll add that to the Rcpp-FAQ now.
>>
>> Note though that here I simply assigned PKG_CXXFLAGS which had been empty as
>> the Rcpp plugin does not set it. Other plugins may, so you one may have
>> append rather than overwrite.
>>
>> Dirk
>>
>> --
>> "Outside of a dog, a book is a man's best friend. Inside of a dog, it is too
>> dark to read." -- Groucho Marx