* installing *source* package ‘tclust’ ...
** using staged installation
** libs
using C compiler: ‘Debian clang version 17.0.6 (5)’
using C++ compiler: ‘Debian clang version 17.0.6 (5)’
clang++-17  -std=gnu++17 -I"/home/hornik/tmp/R/include" -DNDEBUG -DR_PACKAGE_FILE   -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic -c ML_meal.cpp -o ML_meal.o
clang++-17  -std=gnu++17 -I"/home/hornik/tmp/R/include" -DNDEBUG -DR_PACKAGE_FILE   -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic -c ML_package.cpp -o ML_package.o
clang++-17  -std=gnu++17 -I"/home/hornik/tmp/R/include" -DNDEBUG -DR_PACKAGE_FILE   -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic -c ML_passrng.cpp -o ML_passrng.o
clang++-17  -std=gnu++17 -I"/home/hornik/tmp/R/include" -DNDEBUG -DR_PACKAGE_FILE   -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic -c R_meal.cpp -o R_meal.o
In file included from R_meal.cpp:29:
./R_meal.h:25:17: warning: using directive refers to implicitly-defined namespace 'std'
   25 | using namespace std;
      |                 ^
In file included from R_meal.cpp:56:
/home/hornik/tmp/R/include/R.h:39:11: fatal error: 'cstdlib' file not found
   39 | # include <cstdlib>
      |           ^~~~~~~~~
1 warning and 1 error generated.
make: *** [/home/hornik/tmp/R/etc/Makeconf:198: R_meal.o] Error 1
ERROR: compilation failed for package ‘tclust’
* removing ‘/srv/hornik/tmp/CRAN/tclust.Rcheck/tclust’