diff --git a/Cargo.lock b/Cargo.lock
index bf843975c..5ae58fa20 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -339,7 +339,7 @@ dependencies = [
  "rusoto_credential 0.40.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rusoto_s3 0.40.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustwide 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustwide 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "sass-rs 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "schemamama 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "schemamama_postgres 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1884,7 +1884,7 @@ dependencies = [
 
 [[package]]
 name = "rustwide"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "base64 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3094,7 +3094,7 @@ dependencies = [
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum rusttype 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b8eb11f5b0a98c8eca2fb1483f42646d8c340e83e46ab416f8a063a0fd0eeb20"
-"checksum rustwide 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bbeed4fee09d894d922ecc7f51d2368f8c6e5b11bb63667f5d5d604978436da0"
+"checksum rustwide 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a9663f312745b9a53570c3a2170ba92f9e71a49ac3328e15ed5955dd462eaacb"
 "checksum ryu 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "7153dd96dade874ab973e098cb62fcdbb89a03682e46b144fd09550998d4a4a7"
 "checksum safemem 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e27a8b19b835f7aea908818e871f5cc3a5a186550c30773be987e155e8163d8f"
 "checksum safemem 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8dca453248a96cb0749e36ccdfe2b0b4e54a61bfef89fb97ec621eb8e0a93dd9"
diff --git a/Cargo.toml b/Cargo.toml
index 407769b13..bff8bc3f2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,7 +38,7 @@ tokio = "0.1"
 systemstat = "0.1.4"
 prometheus = { version = "0.7.0", default-features = false }
 lazy_static = "1.0.0"
-rustwide = "0.4.0"
+rustwide = "0.5.0"
 tempdir = "0.3"
 
 # iron dependencies
diff --git a/src/docbuilder/rustwide_builder.rs b/src/docbuilder/rustwide_builder.rs
index ed2954fcc..62782e9ca 100644
--- a/src/docbuilder/rustwide_builder.rs
+++ b/src/docbuilder/rustwide_builder.rs
@@ -9,8 +9,10 @@ use postgres::Connection;
 use rustc_serialize::json::ToJson;
 use rustwide::cmd::{Command, SandboxBuilder};
 use rustwide::logging::{self, LogStorage};
+use rustwide::toolchain::ToolchainError;
 use rustwide::{Build, Crate, Toolchain, Workspace, WorkspaceBuilder};
 use std::borrow::Cow;
+use std::collections::HashSet;
 use std::path::Path;
 use utils::{copy_doc_dir, parse_rustc_version, CargoMetadata};
 use Metadata;
@@ -19,7 +21,6 @@ static USER_AGENT: &str = "docs.rs builder (https://github.com/rust-lang/docs.rs
 static DEFAULT_RUSTWIDE_WORKSPACE: &str = ".rustwide";
 
 static TARGETS: &[&str] = &[
-    "i686-apple-darwin",
     "i686-pc-windows-msvc",
     "i686-unknown-linux-gnu",
     "x86_64-apple-darwin",
@@ -95,12 +96,43 @@ impl RustwideBuilder {
         // Ignore errors if detection fails.
         let old_version = self.detect_rustc_version().ok();
 
+        let mut targets_to_install = TARGETS
+            .iter()
+            .map(|t| t.to_string())
+            .collect::<HashSet<_>>();
+        let installed_targets = match self.toolchain.installed_targets(&self.workspace) {
+            Ok(targets) => targets,
+            Err(err) => {
+                if let Some(&ToolchainError::NotInstalled) = err.downcast_ref::<ToolchainError>() {
+                    Vec::new()
+                } else {
+                    return Err(err);
+                }
+            }
+        };
+
+        // The extra targets are intentionally removed *before* trying to update.
+        //
+        // If a target is installed locally and it goes missing the next update, rustup will block
+        // the update to avoid leaving the system in a broken state. This is not a behavior we want
+        // though when we also remove the target from the list managed by docs.rs: we want that
+        // target gone, and we don't care if it's missing in the next update.
+        //
+        // Removing it beforehand works fine, and prevents rustup from blocking the update later in
+        // the method.
+        for target in installed_targets {
+            if !targets_to_install.remove(&target) {
+                self.toolchain.remove_target(&self.workspace, &target)?;
+            }
+        }
+
         self.toolchain.install(&self.workspace)?;
-        for target in TARGETS {
+
+        for target in &targets_to_install {
             self.toolchain.add_target(&self.workspace, target)?;
         }
-        self.rustc_version = self.detect_rustc_version()?;
 
+        self.rustc_version = self.detect_rustc_version()?;
         if old_version.as_ref().map(|s| s.as_str()) != Some(&self.rustc_version) {
             self.add_essential_files()?;
         }