* installing *source* package 'Rcplex' ... ** package 'Rcplex' successfully unpacked and MD5 sums checked ** using staged installation ** libs make[1]: Entering directory '/d/temp/Rtmpe44pq2/R.INSTALL1e5bc5a043c85/Rcplex/src' gcc -I"D:/RCompile/recent/R/include" -DNDEBUG -D_LP64 -I"/include" -I"d:/rtools42/x86_64-w64-mingw32.static.posix/include" -pedantic -O2 -Wall -std=gnu99 -mfpmath=sse -msse2 -mstackrealign -c Rcplex.c -o Rcplex.o In file included from Rcplex.c:2: Rcplex.h:4:10: fatal error: ilcplex/cplex.h: No such file or directory 4 | #include | ^~~~~~~~~~~~~~~~~ compilation terminated. make[1]: *** [D:/RCompile/recent/R/etc/x64/Makeconf:253: Rcplex.o] Error 1 make[1]: Leaving directory '/d/temp/Rtmpe44pq2/R.INSTALL1e5bc5a043c85/Rcplex/src' ERROR: compilation failed for package 'Rcplex' * removing 'd:/Rcompile/CRANpkg/lib/4.3/Rcplex'