Only use ENCLOS with R (< 4.5.0) #1459
Description
Seen at r-universe after the latest merge, and micro version increase:
Can reproduce with 'R Under development (unstable) (2026-03-04 r89536)' from two days ago:
test_environments.R........... 0 tests using C++ compiler: ‘g++-15 (Ubuntu 15.2.0-4ubuntu4) 15.2.0’
ccache g++-15 -I"/usr/local/lib/R-devel/lib/R/include" -DNDEBUG -I"/tmp/r/Rcpp.Rcheck/Rcpp/include" -I"/tmp/r/Rcpp.Rcheck/Rcpp/tinytest/cpp" -I/usr/local/include -fpic -O3 -Wall -pipe -DBOOST_NO_AUTO_PTR -Wno-parentheses -Wno-ignored-attributes -flto -c Environment.cpp -o Environment.o
In file included from /tmp/r/Rcpp.Rcheck/Rcpp/include/Rcpp.h:39,
from Environment.cpp:22:
/tmp/r/Rcpp.Rcheck/Rcpp/include/Rcpp/Environment.h: In instantiation of ‘Rcpp::Environment_Impl<StoragePolicy> Rcpp::Environment_Impl<StoragePolicy>::parent() const [with StoragePolicy = Rcpp::PreserveStorage]’:
Environment.cpp:137:22: required from here
137 | return env.parent() ;
| ~~~~~~~~~~^~
/tmp/r/Rcpp.Rcheck/Rcpp/include/Rcpp/Environment.h:392:44: error: ‘ENCLOS’ was not declared in this scope
392 | return Environment_Impl( ENCLOS(Storage::get__()) ) ;
| ~~~~~~^~~~~~~~~~~~~~~~~~
make: *** [/usr/local/lib/R-devel/lib/R/etc/Makeconf:199: Environment.o] Error 1
Error in Rcpp::sourceCpp("cpp/Environment.cpp") :
Error 1 occurred building shared library.
Calls: <Anonymous> ... run_test_dir -> lapply -> FUN -> eval -> eval -> <Anonymous>
In addition: Warning messages:
1: No function found for Rcpp::export attribute at file4060d457ff1ac.cpp:5
2: In sourceCpp(code = code, env = env, rebuild = rebuild, cacheDir = cacheDir, :
No Rcpp::export attributes or RCPP_MODULE declarations found in source
Execution halted
and with a freshly updated R-devel with 'R Under development (unstable) (2026-03-06 r89558)'
There is also
test_cppfunction_errors.R..... 1 tests OK using C++ compiler: ‘g++-15 (Ubuntu 15.2.0-4ubuntu4) 15.2.0’
ccache g++-15 -I"/usr/local/lib/R-devel/lib/R/include" -DNDEBUG -I"/tmp/r/Rcpp.Rcheck/Rcpp/include" -I"/tmp/r/RtmpqqIOpf/working_dir/RtmpumNq15/sourceCpp-x86_64-pc-linux-gnu-1.1.1.5" -I/usr/local/include
-fpic -O3 -Wall -pipe -DBOOST_NO_AUTO_PTR -Wno-parentheses -Wno-ignored-attributes -flto -c file481939123d30.cpp -o file481939123d30.o
file481939123d30.cpp:33:17: error: redefinition of ‘SEXPREC* sourceCpp_27_foo()’
33 | RcppExport SEXP sourceCpp_27_foo() {
| ^~~~~~~~~~~~~~~~
file481939123d30.cpp:23:17: note: ‘SEXPREC* sourceCpp_27_foo()’ previously defined here
23 | RcppExport SEXP sourceCpp_27_foo() {
| ^~~~~~~~~~~~~~~~
make: *** [/usr/local/lib/R-devel/lib/R/etc/Makeconf:199: file481939123d30.o] Error 1
test_cppfunction_errors.R..... 2 tests OK 1.3s