diff --git a/Cargo.lock b/Cargo.lock
index 7ed935d1b04..b82576568df 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -28,7 +28,7 @@ dependencies = [
  "tar 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempdir 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "term 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "toml 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "toml 0.1.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -434,7 +434,7 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.1.28"
+version = "0.1.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "rustc-serialize 0.3.18 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/Cargo.toml b/Cargo.toml
index 43dca3be7db..996bc04e143 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -40,7 +40,7 @@ semver = "0.2.2"
 tar = "0.4"
 tempdir = "0.3"
 term = "0.4.4"
-toml = "0.1"
+toml = "0.1.29"
 url = "1.1"
 winapi = "0.2"
 
diff --git a/src/cargo/ops/lockfile.rs b/src/cargo/ops/lockfile.rs
index 41b6ac4b8d6..f24fe5bd571 100644
--- a/src/cargo/ops/lockfile.rs
+++ b/src/cargo/ops/lockfile.rs
@@ -22,7 +22,7 @@ pub fn load_pkg_lockfile(pkg: &Package, config: &Config)
     }));
 
     (|| {
-        let table = toml::Value::Table(try!(cargo_toml::parse(&s, f.path())));
+        let table = toml::Value::Table(try!(cargo_toml::parse(&s, f.path(), config)));
         let mut d = toml::Decoder::new(table);
         let v: resolver::EncodableResolve = try!(Decodable::decode(&mut d));
         Ok(Some(try!(v.to_resolve(pkg, config))))
diff --git a/src/cargo/util/config.rs b/src/cargo/util/config.rs
index b03b6837902..53ad520e609 100644
--- a/src/cargo/util/config.rs
+++ b/src/cargo/util/config.rs
@@ -330,7 +330,9 @@ impl Config {
         try!(walk_tree(&self.cwd, |mut file, path| {
             let mut contents = String::new();
             try!(file.read_to_string(&mut contents));
-            let table = try!(cargo_toml::parse(&contents, &path).chain_error(|| {
+            let table = try!(cargo_toml::parse(&contents,
+                                               &path,
+                                               self).chain_error(|| {
                 human(format!("could not parse TOML configuration in `{}`",
                               path.display()))
             }));
@@ -717,7 +719,7 @@ pub fn set_config(cfg: &Config,
     };
     let mut contents = String::new();
     let _ = file.read_to_string(&mut contents);
-    let mut toml = try!(cargo_toml::parse(&contents, file.path()));
+    let mut toml = try!(cargo_toml::parse(&contents, file.path(), cfg));
     toml.insert(key.to_string(), value.into_toml());
 
     let contents = toml::Value::Table(toml).to_string();
diff --git a/src/cargo/util/toml.rs b/src/cargo/util/toml.rs
index 207e22b7db2..4d19b9d70fb 100644
--- a/src/cargo/util/toml.rs
+++ b/src/cargo/util/toml.rs
@@ -114,7 +114,7 @@ pub fn to_manifest(contents: &[u8],
     let contents = try!(str::from_utf8(contents).map_err(|_| {
         human(format!("{} is not valid UTF-8", manifest.display()))
     }));
-    let root = try!(parse(contents, &manifest));
+    let root = try!(parse(contents, &manifest, config));
     let mut d = toml::Decoder::new(toml::Value::Table(root));
     let manifest: TomlManifest = try!(Decodable::decode(&mut d).map_err(|e| {
         human(e.to_string())
@@ -157,15 +157,33 @@ pub fn to_manifest(contents: &[u8],
     }
 }
 
-pub fn parse(toml: &str, file: &Path) -> CargoResult<toml::Table> {
-    let mut parser = toml::Parser::new(&toml);
-    if let Some(toml) = parser.parse() {
+pub fn parse(toml: &str,
+             file: &Path,
+             config: &Config) -> CargoResult<toml::Table> {
+    let mut first_parser = toml::Parser::new(&toml);
+    if let Some(toml) = first_parser.parse() {
         return Ok(toml);
     }
+
+    let mut second_parser = toml::Parser::new(toml);
+    second_parser.set_require_newline_after_table(false);
+    if let Some(toml) = second_parser.parse() {
+        let msg = format!("\
+TOML file found which contains invalid syntax and will soon not parse
+at `{}`.
+
+The TOML spec requires newlines after table definitions (e.g. `[a] b = 1` is
+invalid), but this file has a table header which does not have a newline after
+it. A newline needs to be added and this warning will soon become a hard error
+in the future.", file.display());
+        try!(config.shell().warn(&msg));
+        return Ok(toml)
+    }
+
     let mut error_str = format!("could not parse input as TOML\n");
-    for error in parser.errors.iter() {
-        let (loline, locol) = parser.to_linecol(error.lo);
-        let (hiline, hicol) = parser.to_linecol(error.hi);
+    for error in first_parser.errors.iter() {
+        let (loline, locol) = first_parser.to_linecol(error.lo);
+        let (hiline, hicol) = first_parser.to_linecol(error.hi);
         error_str.push_str(&format!("{}:{}:{}{} {}\n",
                                     file.display(),
                                     loline + 1, locol + 1,
diff --git a/tests/bad-config.rs b/tests/bad-config.rs
index b88ea2f6bfe..63abb529f73 100644
--- a/tests/bad-config.rs
+++ b/tests/bad-config.rs
@@ -479,3 +479,30 @@ warning: dependency (foo) specified without providing a local path, Git reposito
 to use. This will be considered an error in future versions
 "));
 }
+
+#[test]
+fn invalid_toml_historically_allowed_is_warned() {
+    let p = project("empty_deps")
+    .file("Cargo.toml", r#"
+        [package]
+        name = "empty_deps"
+        version = "0.0.0"
+        authors = []
+    "#)
+    .file(".cargo/config", r#"
+        [foo] bar = 2
+    "#)
+    .file("src/main.rs", "fn main() {}");
+
+    assert_that(p.cargo_process("build"),
+                execs().with_status(0).with_stderr("\
+warning: TOML file found which contains invalid syntax and will soon not parse
+at `[..]config`.
+
+The TOML spec requires newlines after table definitions (e.g. `[a] b = 1` is
+invalid), but this file has a table header which does not have a newline after
+it. A newline needs to be added and this warning will soon become a hard error
+in the future.
+[COMPILING] empty_deps v0.0.0 ([..])
+"));
+}
diff --git a/tests/path.rs b/tests/path.rs
index 97cc213225a..574851e9387 100644
--- a/tests/path.rs
+++ b/tests/path.rs
@@ -256,8 +256,10 @@ fn no_rebuild_dependency() {
             version = "0.5.0"
             authors = ["wycats@example.com"]
 
-            [[bin]] name = "foo"
-            [dependencies.bar] path = "bar"
+            [[bin]]
+            name = "foo"
+            [dependencies.bar]
+            path = "bar"
         "#)
         .file("src/foo.rs", r#"
             extern crate bar;
@@ -270,7 +272,8 @@ fn no_rebuild_dependency() {
             version = "0.5.0"
             authors = ["wycats@example.com"]
 
-            [lib] name = "bar"
+            [lib]
+            name = "bar"
         "#)
         .file("bar/src/bar.rs", r#"
             pub fn bar() {}