Make it possible to override RUBY_TARGET (#512)

* Revert "Append -gnu to RUBY_TARGET for GNU Linux builds (#511)"

This reverts commit 798fad1.

* Make it possible to override RUBY_TARGET

Previously if you attempt to run `rb-sys-dock --platform x86_64-linux-gnu`
the `RUBY_TARGET` was hard-coded to `x86_64-linux`. Now this can
be overriden by the `rb-sys-dock` so that the `--platform` argument
can work with `x86_64-linux` or `x86_64-linux-gnu`.

docker/Dockerfile.aarch64-linux

@@ -1,7 +1,7 @@
 # Ensure this version matches the rack-compiler-version in Gemfile
 FROM ghcr.io/rake-compiler/rake-compiler-dock-image:1.9.1-mri-aarch64-linux
 
-ENV RUBY_TARGET="aarch64-linux-gnu" \
+ENV RUBY_TARGET="aarch64-linux" \
     RUST_TARGET="aarch64-unknown-linux-gnu" \
     RUSTUP_DEFAULT_TOOLCHAIN="stable" \
     PKG_CONFIG_ALLOW_CROSS="1" \

docker/Dockerfile.arm-linux

@@ -1,7 +1,7 @@
 # Ensure this version matches the rack-compiler-version in Gemfile
 FROM ghcr.io/rake-compiler/rake-compiler-dock-image:1.9.1-mri-arm-linux
 
-ENV RUBY_TARGET="arm-linux-gnu" \
+ENV RUBY_TARGET="arm-linux" \
     RUST_TARGET="arm-unknown-linux-gnueabihf" \
     RUSTUP_DEFAULT_TOOLCHAIN="stable" \
     PKG_CONFIG_ALLOW_CROSS="1" \

docker/Dockerfile.x86-linux

@@ -1,7 +1,7 @@
 # Ensure this version matches the rack-compiler-version in Gemfile
 FROM ghcr.io/rake-compiler/rake-compiler-dock-image:1.9.1-mri-x86-linux
 
-ENV RUBY_TARGET="x86-linux-gnu" \
+ENV RUBY_TARGET="x86-linux" \
     RUST_TARGET="i686-unknown-linux-gnu" \
     RUSTUP_DEFAULT_TOOLCHAIN="stable" \
     PKG_CONFIG_ALLOW_CROSS="1" \

docker/Dockerfile.x86_64-linux

@@ -1,7 +1,7 @@
 # Ensure this version matches the rack-compiler-version in Gemfile
 FROM ghcr.io/rake-compiler/rake-compiler-dock-image:1.9.1-mri-x86_64-linux
 
-ENV RUBY_TARGET="x86_64-linux-gnu" \
+ENV RUBY_TARGET="x86_64-linux" \
     RUST_TARGET="x86_64-unknown-linux-gnu" \
     RUSTUP_DEFAULT_TOOLCHAIN="stable" \
     PKG_CONFIG_ALLOW_CROSS="1" \

docker/setup/rubybashrc.sh

@@ -52,7 +52,6 @@ main() {
   echo "export PATH=\"/usr/local/cargo/bin:\$PATH\"" >> "$OUTFILE"
   echo "export RUSTUP_HOME=\"$RUSTUP_HOME\"" >> "$OUTFILE"
   echo "export CARGO_HOME=\"$CARGO_HOME\"" >> "$OUTFILE"
-  echo "export RUBY_TARGET=\"$RUBY_TARGET\"" >> "$OUTFILE"
   echo "export RCD_PLATFORM=\"$RUBY_TARGET\"" >> "$OUTFILE"
   echo "export RUST_TARGET=\"$RUST_TARGET\"" >> "$OUTFILE"
   echo "export RUSTUP_DEFAULT_TOOLCHAIN=\"$RUSTUP_DEFAULT_TOOLCHAIN\"" >> "$OUTFILE"

gem/exe/rb-sys-dock

@@ -391,6 +391,7 @@ def rcd(input_args)
       -e RB_SYS_DOCK_TMPDIR="/tmp/rb-sys-dock" \
       -e RB_SYS_CARGO_TARGET_DIR=#{tmp_target_dir.inspect} \
       -e RUBY_CC_VERSION="#{ruby_versions}" \
+      -e RUBY_TARGET="#{OPTIONS.fetch(:platform)}" \
       -e RAKEOPT \
       -e TERM \
       -w #{working_directory} \