cfg: linkcheck only on x86-64 linux

src/ci/docker/armhf-gnu/Dockerfile

@@ -13,8 +13,6 @@ RUN apt-get update -y && apt-get install -y --no-install-recommends \
       git \
       libc6-dev \
       libc6-dev-armhf-cross \
-      libssl-dev \
-      pkg-config \
       make \
       python2.7 \
       qemu-system-arm \

src/ci/docker/asmjs/Dockerfile

@@ -11,8 +11,6 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  libssl-dev \
-  pkg-config \
   xz-utils
 
 COPY scripts/emscripten.sh /scripts/

src/ci/docker/i686-gnu-nopt/Dockerfile

@@ -11,8 +11,6 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  libssl-dev \
-  pkg-config \
   xz-utils
 
 

src/ci/docker/i686-gnu/Dockerfile

@@ -11,8 +11,6 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  libssl-dev \
-  pkg-config \
   xz-utils
 
 

src/tools/rustbook/Cargo.toml

@@ -7,7 +7,6 @@ edition = "2018"
 
 [dependencies]
 clap = "2.25.0"
-mdbook-linkcheck = "0.3.0"
 failure = "0.1"
 
 [dependencies.mdbook]
@@ -20,3 +19,6 @@ package = "mdbook"
 version = "0.1.7"
 default-features = false
 features = ["search"]
+
+[target.'cfg(all(target_arch = "x86_64", target_os = "linux"))'.dependencies]
+mdbook-linkcheck = "0.3.0"

src/tools/rustbook/src/main.rs

@@ -14,10 +14,12 @@ use mdbook::MDBook;
 use mdbook::errors::{Result as Result3};
 use mdbook::renderer::RenderContext;
 
-use mdbook_linkcheck;
-use mdbook_linkcheck::errors::BrokenLinks;
+#[cfg(all(target_arch = "x86_64", target_os = "linux"))]
+use mdbook_linkcheck::{self, errors::BrokenLinks};
 use failure::Error;
 
+#[cfg(not(all(target_arch = "x86_64", target_os = "linux")))]
+use failure::bail;
 
 fn main() {
     let d_message = "-d, --dest-dir=[dest-dir]
@@ -90,6 +92,7 @@ fn main() {
     };
 }
 
+#[cfg(all(target_arch = "x86_64", target_os = "linux"))]
 pub fn linkcheck(args: &ArgMatches<'_>) -> Result<(), Error> {
     let book_dir = get_book_dir(args);
     let book = MDBook::load(&book_dir).unwrap();
@@ -99,6 +102,11 @@ pub fn linkcheck(args: &ArgMatches<'_>) -> Result<(), Error> {
     mdbook_linkcheck::check_links(&render_ctx)
 }
 
+#[cfg(not(all(target_arch = "x86_64", target_os = "linux")))]
+pub fn linkcheck(args: &ArgMatches<'_>) -> Result<(), Error> {
+    bail!("mdbook-linkcheck only works on x86_64 linux targets.");
+}
+
 // Build command implementation
 pub fn build_1(args: &ArgMatches<'_>) -> Result1<()> {
     let book_dir = get_book_dir(args);