When using C++ compiler, R headers cannot be included from "extern C" blocks, because they include some C++ headers (which may e.g. have templates, which cannot be with a C linkage). R headers, after including C++ headers, would themselves use "extern C" when needed. This problem prevents the package from building with LLVM 17 clang.
I've also fixed the error and warning calls to always pass a format string, to avoid warnings.
When using C++ compiler, R headers cannot be included from "extern C" blocks, because they include some C++ headers (which may e.g. have templates, which cannot be with a C linkage). R headers, after including C++ headers, would themselves use "extern C" when needed. This problem prevents the package from building with LLVM 17 clang.
I've also fixed the error and warning calls to always pass a format string, to avoid warnings.