Merge pull request #1069 from bsilver8192/link-order-note

Add a note about linking order

book/src/build/other.md

@@ -48,6 +48,12 @@ When linking a binary which contains mixed Rust and C++ code, you will have to
 choose between using the Rust toolchain (`rustc`) or the C++ toolchain which you
 may already have extensively tuned.
 
+The generated C++ code and the Rust code generated by the procedural macro both
+depend on each other. Simple examples may only require one or the other, but in
+general your linking will need to handle both directions. For some linkers, such
+as llvm-ld, this is not a problem at all. For others, such as GNU ld, flags like
+`--start-lib`/`--end-lib` may help.
+
 Rust does not generate simple standalone `.o` files, so you can't just throw the
 Rust-generated code into your existing C++ toolchain linker. Instead you need to
 choose one of these options: