From 4660285984dff8549bb5589f8fa14e3df88bc5b2 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge.aparicio@ferrous-systems.com>
Date: Tue, 8 Dec 2020 17:51:08 +0100
Subject: [PATCH 1/3] don't set RUSTFLAGS in aarch64-musl image

---
 docker/Dockerfile.aarch64-unknown-linux-musl |  5 ++---
 docker/aarch64-linux-musl-gcc.sh             | 23 ++++++++++++++++++++
 2 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100755 docker/aarch64-linux-musl-gcc.sh

diff --git a/docker/Dockerfile.aarch64-unknown-linux-musl b/docker/Dockerfile.aarch64-unknown-linux-musl
index 507de85d6..255471268 100644
--- a/docker/Dockerfile.aarch64-unknown-linux-musl
+++ b/docker/Dockerfile.aarch64-unknown-linux-musl
@@ -21,10 +21,9 @@ RUN ln -sf \
     /usr/local/aarch64-linux-musl/lib/ld-musl-aarch64.so.1
 ENV QEMU_LD_PREFIX=/usr/local/aarch64-linux-musl
 
-# Workaround for https://github.com/rust-lang/rust/issues/46651
-ENV RUSTFLAGS="-C link-arg=-lgcc"
+COPY aarch64-linux-musl-gcc.sh /usr/bin/
 
-ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_MUSL_LINKER=aarch64-linux-musl-gcc \
+ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_MUSL_LINKER=aarch64-linux-musl-gcc.sh \
     CARGO_TARGET_AARCH64_UNKNOWN_LINUX_MUSL_RUNNER=qemu-aarch64 \
     CC_aarch64_unknown_linux_musl=aarch64-linux-musl-gcc \
     CXX_aarch64_unknown_linux_musl=aarch64-linux-musl-g++ \
diff --git a/docker/aarch64-linux-musl-gcc.sh b/docker/aarch64-linux-musl-gcc.sh
new file mode 100755
index 000000000..635641ff8
--- /dev/null
+++ b/docker/aarch64-linux-musl-gcc.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# this linker wrapper works around issue https://github.com/rust-lang/rust/issues/46651
+# which affects toolchains older than 1.48
+# older toolchains require the `-lgcc` linker flag otherwise they fail to link
+
+set -euo pipefail
+
+main() {
+    local release=$(rustc -Vv | grep '^release:' | cut -d ':' -f2)
+    # NOTE we assume `major` is always "1"
+    local minor=$(echo $release | cut -d '.' -f2)
+
+    if (( $minor >= 48 )); then
+        # no workaround
+        aarch64-linux-musl-gcc "${@}"
+    else
+        # apply workaround
+        aarch64-linux-musl-gcc "${@}" -lgcc
+    fi
+}
+
+main "${@}"

From cfa30b8d7c72b388794c37caca129f5006e7b569 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge.aparicio@ferrous-systems.com>
Date: Tue, 8 Dec 2020 18:23:37 +0100
Subject: [PATCH 2/3] make shellcheck happy

---
 docker/aarch64-linux-musl-gcc.sh | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/docker/aarch64-linux-musl-gcc.sh b/docker/aarch64-linux-musl-gcc.sh
index 635641ff8..6d0aa1e63 100755
--- a/docker/aarch64-linux-musl-gcc.sh
+++ b/docker/aarch64-linux-musl-gcc.sh
@@ -7,11 +7,13 @@
 set -euo pipefail
 
 main() {
-    local release=$(rustc -Vv | grep '^release:' | cut -d ':' -f2)
+    local release=
+    release=$(rustc -Vv | grep '^release:' | cut -d ':' -f2)
     # NOTE we assume `major` is always "1"
-    local minor=$(echo $release | cut -d '.' -f2)
+    local minor=
+    minor=$(echo "$release" | cut -d '.' -f2)
 
-    if (( $minor >= 48 )); then
+    if (( minor >= 48 )); then
         # no workaround
         aarch64-linux-musl-gcc "${@}"
     else

From 35ec4e157a4fa4250c3ccf5beab2b50d3ea13ee0 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge.aparicio@ferrous-systems.com>
Date: Fri, 11 Dec 2020 18:36:32 +0100
Subject: [PATCH 3/3] use runner setting specified in Cross.toml

---
 src/docker.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/docker.rs b/src/docker.rs
index a07bd3c12..2b6412304 100644
--- a/src/docker.rs
+++ b/src/docker.rs
@@ -103,7 +103,7 @@ pub fn run(target: &Target,
 
     cmd.args(args);
 
-    let runner = None;
+    let mut runner = None;
 
     let mut docker = docker_command("run")?;
 
@@ -140,6 +140,8 @@ pub fn run(target: &Target,
                 docker.args(&["-e", &format!("{}={}", var, mount_path.display())]);
             }
         }
+
+        runner = toml.runner(target)?;
     }
 
     docker.args(&["-e", "PKG_CONFIG_ALLOW_CROSS=1"]);