Fix staticlib outputs linking to blank archives

When creating a staticlib, it unzips all static archives it finds and then
inserts the files manually into the output file. This process is done through
`ar`, and `ar` doesn't like if you specify you want to add files and you don't
give it any files.

This case arose whenever you linked to an archive that didn't have any contents
or all of the contents were filtered out. This just involved ignoring the case
where the number of inputs we have is 0, because we don't have any files to add
anyway.

diff --git a/src/librustc/back/archive.rs b/src/librustc/back/archive.rs
index 18aef17b9eb77031b3ff9cdfe745b236c98b1643..406c3026614dc8b84b4a21825a4c3073ec61e4cf 100644 (file)
--- a/src/librustc/back/archive.rs
+++ b/src/librustc/back/archive.rs
@@ -173,6 +173,7 @@ fn add_archive(&mut self, archive: &Path, name: &str,
             if_ok!(fs::rename(file, &new_filename));
             inputs.push(new_filename);
         }
+        if inputs.len() == 0 { return Ok(()) }
 
         // Finally, add all the renamed files to this archive
         let mut args = ~[&self.dst];

diff --git a/src/test/run-make/staticlib-blank-lib/Makefile b/src/test/run-make/staticlib-blank-lib/Makefile
new file mode 100644 (file)
index 0000000..c56d121
--- /dev/null
+++ b/src/test/run-make/staticlib-blank-lib/Makefile
@@ -0,0 +1,6 @@
+-include ../tools.mk
+
+all:
+       ar crus libfoo.a foo.rs
+       ar d libfoo.a foo.rs
+       $(RUSTC) foo.rs

diff --git a/src/test/run-make/staticlib-blank-lib/foo.rs b/src/test/run-make/staticlib-blank-lib/foo.rs
new file mode 100644 (file)
index 0000000..b3d9c00
--- /dev/null
+++ b/src/test/run-make/staticlib-blank-lib/foo.rs
@@ -0,0 +1,16 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[crate_type = "staticlib"];
+
+#[link(name = "foo", kind = "static")]
+extern {}
+
+fn main() {}