[Rcpp-devel] question re: LdFlags, RcppLdFlags

[Romain Francois]

Le 10/10/13 02:41, Dirk Eddelbuettel a écrit :
>
> (Combining two of your emails)
>
> On 10 October 2013 at 01:08, Romain Francois wrote:
> | RcppGSL does not export its LdFlags, if it did, you'd see the warning
> | when you load it.
>
> Good catch ... but turns out I don't (to my surprise).

Yes; My mistake. almost 3 am here :/

> It seems to work. Maybe NAMESPACE really do help.  Full log at bottom.
>
> | Why would you import Rcpp's LdFlags inside RcppGSL's namespace, you
> | don't use it there.
>
> R CMD check did complain, I guess it must grep for src/ to find it in
> Makevars. Once I imported the complaint went away.

If this fixes something for you, that's fine. I just don't get why you 
would import something you don't use.

What makes sense to me now is both Rcpp and RcppGSL exporting their own 
LdFlags. Having RcppGSL import the one from Rcpp makes no sense to me. 
But if it makes R CMD check happy.

Soon they are going to rename it R CMD ChuckNorris

> On 10 October 2013 at 01:18, Romain Francois wrote:
> | > That's pretty.  For all the Rcpp-using package, we can assume Rcpp to be
> | > there so it may as well pivot over and call a plugin from 'foo'.
> |
> | I think it is worth looking in that direction.
>
> We'll see if we need it. Kevin's point etc.
>
> | > The other immediate defensive way would be to use NAMESPACE etc on the client
> | > package and not load Rcpp and Rcpp$foo but just importFrom() etc what is needed.
> |
> | Maybe that works.
>
> Generally speaking, and as I understand recent r-devel threads, Imports: and
> importFrom(...) is how we are supposed to work with NAMESPACEs now.  That is
> also what I did here, and what you roundly mocked one email ago (see above).

I'm sorry you preceived mockery.

> I am sure we'll find a way to sort it all out.
>
> Dirk
>
> Log below
>
> edd at max:~/svn/rcpp/pkg$ svn di RcppGSL     ## now exporting LdFlags in RcppGSL
> Index: RcppGSL/NAMESPACE
> ===================================================================
> --- RcppGSL/NAMESPACE	(revision 4567)
> +++ RcppGSL/NAMESPACE	(working copy)
> @@ -3,7 +3,8 @@
>   importFrom(utils,assignInNamespace)
>   importFrom(Rcpp,LdFlags)
>   export(fastLmPure,
> -       fastLm)
> +       fastLm,
> +       LdFlags)
>   S3method(fastLm, default)
>   S3method(fastLm, formula)
>   S3method(predict, fastLm)
> edd at max:~/svn/rcpp/pkg$ R CMD INSTALL RcppGSL_0.2.0.3.tar.gz ## using rebuilt tar.gz
> * installing to library ‘/usr/local/lib/R/site-library’
> * installing *source* package ‘RcppGSL’ ...
> checking for gcc... gcc
> checking for C compiler default output file name... a.out
> checking whether the C compiler works... yes
> checking whether we are cross compiling... no
> checking for suffix of executables...
> checking for suffix of object files... o
> checking whether we are using the GNU C compiler... yes
> checking whether gcc accepts -g... yes
> checking for gcc option to accept ISO C89... none needed
> checking for gsl-config... /usr/bin/gsl-config
> checking for Rscript... yes
> configure: creating ./config.status
> config.status: creating src/Makevars
> ** libs
> ccache g++-4.7 -I/usr/share/R/include -DNDEBUG -I/usr/include -I../inst/include  -I"/usr/local/lib/R/site-library/Rcpp/include"   -fpic  -g -O3 -Wall -pipe -Wno-unused -pedantic  -c fastLm.cpp -o fastLm.o
> g++-4.7 -shared -o RcppGSL.so fastLm.o -L/usr/lib -lgsl -lgslcblas -lm -L/usr/local/lib/R/site-library/Rcpp/lib -lRcpp -Wl,-rpath,/usr/local/lib/R/site-library/Rcpp/lib -L/usr/lib/R/lib -lR
> installing to /usr/local/lib/R/site-library/RcppGSL/libs
> ** R
> ** inst
> ** preparing package for lazy loading
> ** help
> *** installing help indices
> ** building package indices
> ** installing vignettes
> ** testing if installed package can be loaded
> * DONE (RcppGSL)
> edd at max:~/svn/rcpp/pkg$ R
>
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>
> Careful now, or I'll get into a rant about how much you pay for ArcGIS and whether you are getting value for money if bugs become 'well-known'! Bugs in R
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>     -- Barry Rowlingson (in response to a request for rgdal to work around a well-known bug in ArcGIS)
>        R-SIG-Geo (March 2012)
>
> R> library(RcppGSL)          ## no warning !!
> R> LdFlags                   ## local
> function (print = TRUE)
> {
>      if (print)
>          cat(.pkgglobalenv$gsl_libs)
>      else .pkgglobalenv$gsl_libs
> }
> <environment: namespace:RcppGSL>
> R> Rcpp::LdFlags             ## remote from Rcpp
> function (static = staticLinking())
> {
>      cat(RcppLdFlags(static = static))
> }
> <environment: namespace:Rcpp>
> R>
>


-- 
Romain Francois
Professional R Enthusiast
+33(0) 6 28 91 30 30