libboard: use --cfg

artiq/firmware/libboard/Cargo.toml

@@ -2,6 +2,7 @@
 authors = ["M-Labs"]
 name = "board"
 version = "0.0.0"
+build = "build.rs"
 
 [lib]
 name = "board"

artiq/firmware/libboard/build.rs

@@ -0,0 +1,17 @@
+use std::env;
+use std::path::Path;
+use std::io::{BufRead, BufReader};
+use std::fs::File;
+
+fn main() {
+    let out_dir = env::var("BUILDINC_DIRECTORY").unwrap();
+    let cfg_path = Path::new(&out_dir).join("generated").join("rust-cfg");
+    println!("cargo:rerun-if-changed={}", cfg_path.to_str().unwrap());
+
+    let f = BufReader::new(File::open(&cfg_path).unwrap());
+    for line in f.lines() {
+        println!("cargo:rustc-cfg={}", line.unwrap());
+    }
+
+    println!("cargo:rustc-cfg={}", "board");
+}

artiq/firmware/libboard/lib.rs

@@ -11,15 +11,15 @@ include!(concat!(env!("BUILDINC_DIRECTORY"), "/generated/csr.rs"));
 pub mod spr;
 pub mod irq;
 pub mod clock;
-// XXX #[cfg(has_ad9516)]
+#[cfg(has_ad9516)]
 #[allow(dead_code)]
 mod ad9516_reg;
-// XXX #[cfg(has_ad9516)]
+#[cfg(has_ad9516)]
 pub mod ad9516;
-// XXX #[cfg(has_converter_spi)]
+#[cfg(has_converter_spi)]
 #[allow(dead_code)]
 mod ad9154_reg;
-// XXX #[cfg(has_converter_spi)]
+#[cfg(has_converter_spi)]
 pub mod ad9154;
 
 extern {