rustc: add target, target-cpu and print examples (#4320)

pages/common/rustc.md

@@ -15,3 +15,19 @@
 - Compile with debugging information:
 
 `rustc -g {{file.rs}}`
+
+- Compile with architecture-specific optimizations for the current CPU:
+
+`rustc -C target-cpu=native {{path/to/file.rs}}`
+
+- Display architecture-specific optimizations for the current CPU:
+
+`rustc -C target-cpu=native --print cfg`
+
+- Display target list:
+
+`rustc --print target-list`
+
+- Compile for a specific target:
+
+`rustc --target {{target_triple}} {{path/to/file.rs}}`