From ac094e893bf94d7d6d267abaedfa89bbb60e9ed6 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Sun, 7 Sep 2014 11:48:35 -0700
Subject: [PATCH] Don't deadlock when a dep has no libs

---
 src/cargo/ops/cargo_rustc/mod.rs |  4 ++++
 tests/test_cargo_compile.rs      | 25 +++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/src/cargo/ops/cargo_rustc/mod.rs b/src/cargo/ops/cargo_rustc/mod.rs
index f9cb09631..1ff4190a3 100644
--- a/src/cargo/ops/cargo_rustc/mod.rs
+++ b/src/cargo/ops/cargo_rustc/mod.rs
@@ -81,6 +81,10 @@ pub fn compile_targets<'a>(env: &str, targets: &[&'a Target], pkg: &'a Package,
             cx.is_relevant_target(*target)
         }).collect::<Vec<&Target>>();
 
+        if targets.len() == 0 {
+            return Err(human(format!("Package `{}` has no library targets", dep)))
+        }
+
         try!(compile(targets.as_slice(), dep, &mut cx, &mut queue));
     }
 
diff --git a/tests/test_cargo_compile.rs b/tests/test_cargo_compile.rs
index 9c754cc34..efaa330c8 100644
--- a/tests/test_cargo_compile.rs
+++ b/tests/test_cargo_compile.rs
@@ -1641,3 +1641,28 @@ test!(rebuild_preserves_out_dir {
 {compiling} foo v0.0.0 ({url})
 ", compiling = COMPILING, url = foo.url())));
 })
+
+test!(dep_no_libs {
+    let foo = project("foo")
+        .file("Cargo.toml", r#"
+            [package]
+            name = "foo"
+            version = "0.0.0"
+            authors = []
+
+            [dependencies.bar]
+            path = "bar"
+        "#)
+        .file("src/lib.rs", "pub fn bar() -> int { 1 }")
+        .file("bar/Cargo.toml", r#"
+            [package]
+            name = "bar"
+            version = "0.0.0"
+            authors = []
+        "#)
+        .file("bar/src/main.rs", "");
+    assert_that(foo.cargo_process("build"),
+                execs().with_status(101)
+                       .with_stderr("\
+Package `bar v0.0.0 ([..])` has no library targets"));
+})
-- 
2.30.2