From 1a3f69d3b852ce06117d7dbeb36a58ef3e4ade35 Mon Sep 17 00:00:00 2001
From: Kleis Auke Wolthuizen <github@kleisauke.nl>
Date: Sun, 28 Nov 2021 16:43:18 +0100
Subject: [PATCH] [WiP] Enable c feature of Rust's compiler-builtins crate

---
 build/lin.sh                |  9 +++++++--
 linux-arm64/Dockerfile      |  8 +++++++-
 linux-musl-arm64/Dockerfile | 10 ++++++++--
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/build/lin.sh b/build/lin.sh
index 635732b0..0275d3f4 100755
--- a/build/lin.sh
+++ b/build/lin.sh
@@ -188,7 +188,7 @@ if [ "$ALL_AT_VERSION_LATEST" = "false" ]; then exit 1; fi
 # Download and build dependencies from source
 
 if [ "$DARWIN" = true ]; then
-  curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
+  $CURL --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
     | sh -s -- -y --no-modify-path --profile minimal ${DARWIN_ARM:+--default-toolchain nightly}
   if [ "$DARWIN_ARM" = true ]; then
     ${CARGO_HOME}/bin/rustup component add rust-src 
@@ -198,7 +198,12 @@ if [ "$DARWIN" = true ]; then
     # See: https://github.com/lovell/sharp-libvips/issues/109
     printf "[unstable]\n\
 build-std = [\"std\", \"panic_abort\"]\n\
-build-std-features = [\"panic_immediate_abort\"]" > ${CARGO_HOME}/config.toml
+build-std-features = [\"panic_immediate_abort\", \"compiler-builtins-c\"]" > ${CARGO_HOME}/config.toml
+
+    # `c` feature of the `compiler-builtins` crate needs the compiler-rt sources from LLVM
+    $CURL https://github.com/rust-lang/llvm-project/archive/rustc/13.0-2021-09-30.tar.gz | \
+      tar -xzC ${ROOT} --strip-components 1 llvm-project-rustc-13.0-2021-09-30/compiler-rt
+    export RUST_COMPILER_RT_ROOT="${ROOT}/compiler-rt"
   fi
 fi
 
diff --git a/linux-arm64/Dockerfile b/linux-arm64/Dockerfile
index bd055167..187c62f7 100644
--- a/linux-arm64/Dockerfile
+++ b/linux-arm64/Dockerfile
@@ -42,12 +42,18 @@ RUN \
 RUN \
   printf "[unstable]\n\
 build-std = [\"std\", \"panic_abort\"]\n\
-build-std-features = [\"panic_immediate_abort\"]" > $CARGO_HOME/config.toml
+build-std-features = [\"panic_immediate_abort\", \"compiler-builtins-c\"]" > $CARGO_HOME/config.toml
+
+# `c` feature of the `compiler-builtins` crate needs the compiler-rt sources from LLVM
+RUN \
+  curl -Ls https://github.com/rust-lang/llvm-project/archive/rustc/13.0-2021-09-30.tar.gz | \
+    tar -xzC /root --strip-components 1 llvm-project-rustc-13.0-2021-09-30/compiler-rt
 
 # Compiler settings
 ENV \
   PLATFORM="linux-arm64" \
   CARGO_BUILD_TARGET="aarch64-unknown-linux-gnu" \
+  RUST_COMPILER_RT_ROOT="/root/compiler-rt" \
   FLAGS="-march=armv8-a" \
   MESON="--cross-file=/root/meson.ini"
 
diff --git a/linux-musl-arm64/Dockerfile b/linux-musl-arm64/Dockerfile
index 4c27c44e..c6283e31 100644
--- a/linux-musl-arm64/Dockerfile
+++ b/linux-musl-arm64/Dockerfile
@@ -36,7 +36,7 @@ RUN \
     shared-mime-info \
     texinfo && \
   apk --update --no-cache --repository https://alpine.global.ssl.fastly.net/alpine/edge/community/ add advancecomp && \
-  curl -Ls https://github.com/lovell/aarch64-linux-musl-crosstools/archive/main.tar.gz | tar -hxzC / --strip-components=2 && \
+  curl -Ls https://github.com/lovell/aarch64-linux-musl-crosstools/archive/main.tar.gz | tar -hxzC / --strip-components 2 && \
   ln -s /usr/bin/pkg-config /bin/aarch64-linux-musl-pkg-config && \
   curl https://sh.rustup.rs -sSf | sh -s -- -y \
     --no-modify-path \
@@ -51,7 +51,12 @@ RUN \
 RUN \
   printf "[unstable]\n\
 build-std = [\"std\", \"panic_abort\"]\n\
-build-std-features = [\"panic_immediate_abort\"]" > $CARGO_HOME/config.toml
+build-std-features = [\"panic_immediate_abort\", \"compiler-builtins-c\"]" > $CARGO_HOME/config.toml
+
+# `c` feature of the `compiler-builtins` crate needs the compiler-rt sources from LLVM
+RUN \
+  curl -Ls https://github.com/rust-lang/llvm-project/archive/rustc/13.0-2021-09-30.tar.gz | \
+    tar -xzC /root --strip-components 1 llvm-project-rustc-13.0-2021-09-30/compiler-rt
 
 # Compiler settings
 ENV \
@@ -59,6 +64,7 @@ ENV \
   PLATFORM="linux-musl-arm64" \
   CHOST="aarch64-linux-musl" \
   RUST_TARGET="aarch64-unknown-linux-musl" \
+  RUST_COMPILER_RT_ROOT="/root/compiler-rt" \
   FLAGS="-march=armv8-a" \
   MESON="--cross-file=/root/meson.ini"