Do not compile the stubs in test mode

Test mode requires libtest, which implicity depends on libstd. The stubs
will conflict with libtest whenever we are in test mode. libtest cannot
be used on AVR anyway.

Author: dylanmckay

src/lib.rs

@@ -5,13 +5,6 @@
 
 #![feature(lang_items)]
 
-#[lang = "eh_personality"]
-#[no_mangle]
-pub unsafe extern "C" fn rust_eh_personality() -> () {
-}
-
-#[panic_handler]
-fn panic(_info: &::core::panic::PanicInfo) -> ! {
-    loop {}
-}
 
+#[cfg(not(test))] // Disable the stubs for test because #[no_std] is ignored there because libtest depends on it.
+mod stubs;

src/stubs.rs

@@ -0,0 +1,10 @@
+#[lang = "eh_personality"]
+#[no_mangle]
+pub unsafe extern "C" fn rust_eh_personality() -> () {
+}
+
+#[panic_handler]
+fn panic(_info: &::core::panic::PanicInfo) -> ! {
+    loop {}
+}
+