miri build script: support building miri in debug mode

Author: RalfJung

miri

@@ -1,4 +1,36 @@
 #!/bin/sh
+## Usage
+#
+# COMMANDS
+#
+# ./miri install <flags>:
+# Installs the miri driver and cargo-miri. <flags> are passed to `cargo
+# install`.  Sets up the rpath such that the installed binary should work in any
+# working directory.
+#
+# ./miri build <flags>:
+# Just build miri.  <flags> are passed to `cargo build`.
+#
+# ./miri test <flags>:
+# Build miri, set up a sysroot and then run the test suite. <flags> are passed
+# to the final `cargo test` invocation.
+#
+# ./miri run <flags>:
+# Build miri, set up a sysroot and then run the driver with the given <flags>.
+#
+# All commands also exist in a "-debug" variant (e.g. "./miri run-debug
+# <flags>") which uses debug builds instead of release builds, for faster build
+# times and slower execution times.
+#
+# ENVIRONMENT VARIABLES
+#
+# MIRI_SYSROOT:
+# If already set, the "sysroot setup" step is skipped.
+#
+# CARGO_EXTRA_FLAGS:
+# Pass extra flags to all cargo invocations.
+
+## Preparation
 set -e
 # I'd love to use `jq` for parsing the JSON properly, but macOS is totally underequipped for this kind of work.
 TARGET=$(rustc --print target-spec-json -Z unstable-options | grep llvm-target | cut -d '"' -f 4)
@@ -13,9 +45,9 @@ export RUSTFLAGS="-C link-args=-Wl,-rpath,$SYSROOT/lib/rustlib/$TARGET/lib -C de
 # Build a sysroot and set MIRI_SYSROOT to use it.  Arguments are passed to `cargo miri setup`.
 build_sysroot() {
     # Build once, for the user to see.
-    cargo run --release --bin cargo-miri -- miri setup "$@"
+    cargo run $CARGO_BUILD_FLAGS --bin cargo-miri -- miri setup "$@"
     # Call again, to just set env var.
-    eval $(cargo run --release -q --bin cargo-miri -- miri setup --env "$@")
+    eval $(cargo run $CARGO_BUILD_FLAGS -q --bin cargo-miri -- miri setup --env "$@")
     export MIRI_SYSROOT
 }
 
@@ -48,23 +80,44 @@ find_sysroot() {
 
 ## Main
 
+# Determine command.
 COMMAND="$1"
 shift
 
+# Determine flags passed to all cargo invocations.
 case "$COMMAND" in
-install)
+*-debug)
+    CARGO_INSTALL_FLAGS="--debug $CARGO_EXTRA_FLAGS"
+    CARGO_BUILD_FLAGS="$CARGO_EXTRA_FLAGS"
+    ;;
+*)
+    CARGO_INSTALL_FLAGS="$CARGO_EXTRA_FLAGS"
+    CARGO_BUILD_FLAGS="--release $CARGO_EXTRA_FLAGS"
+    ;;
+esac
+
+# Run command.
+case "$COMMAND" in
+install|install-debug)
     # "--locked" to respect the Cargo.lock file if it exists,
     # "--offline" to avoid querying the registry (for yanked packages).
-    exec cargo "$COMMAND" --path "$(dirname "$0")" --force --locked --offline "$@"
+    exec cargo install --path "$(dirname "$0")" --force --locked --offline "$@"
     ;;
-build)
+build|build-debug)
     # Build, and let caller control flags.
-    exec cargo "$COMMAND" --release "$@"
+    exec cargo build $CARGO_BUILD_FLAGS "$@"
+    ;;
+test|test-debug)
+    # First build and get a sysroot.
+    cargo build $CARGO_BUILD_FLAGS
+    find_sysroot
+    # Then test, and let caller control flags.
+    exec cargo test $CARGO_BUILD_FLAGS "$@"
     ;;
-test|run)
-    # In "run" mode, scan for "--target" to set the "MIRI_TEST_TARGET" env var so
+run|run-debug)
+    # Scan for "--target" to set the "MIRI_TEST_TARGET" env var so
     # that we set the MIRI_SYSROOT up the right way.
-    if [ "$COMMAND" = "run" ] && [ -z "$MIRI_TEST_TARGET" ]; then
+    if [ -z "$MIRI_TEST_TARGET" ]; then
         for ARG in "$@"; do
             if [ "$LAST_ARG" = "--target" ]; then
                 # Found it!
@@ -75,9 +128,9 @@ test|run)
         done
     fi
     # First build and get a sysroot.
-    cargo build --release
+    cargo build $CARGO_BUILD_FLAGS
     find_sysroot
     # Then run the actual command.
-    exec cargo "$COMMAND" --release "$@"
+    exec cargo run $CARGO_BUILD_FLAGS "$@"
     ;;
 esac