v2

tools/gen-compile-commands.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+# Regenerate compile_commands.json for src/bpf/main.bpf.c so clangd sees the
+# same flags the real BPF build uses.
+#
+# scx_cargo prints its computed cflags to the build-script output as a line
+# starting with `scx_utils:clang=`. The include paths in it point into
+# target/<profile>/build/scx_soryu-<hash>/out, and that hash changes whenever
+# the build-script inputs change, so this is generated rather than committed.
+#
+# Run inside the devShell after a build:
+#   cargo build --release && ./tools/gen-compile-commands.sh
+
+set -euo pipefail
+
+cd "$(dirname "$0")/.."
+root="$PWD"
+
+profile="${1:-release}"
+out=$(ls -td "target/$profile"/build/scx_soryu-*/output 2>/dev/null | head -1 || true)
+
+if [ -z "$out" ]; then
+  echo "error: no build-script output under target/$profile/build/." >&2
+  echo "       run 'cargo build --${profile/dev/}' first (inside the devShell)." >&2
+  exit 1
+fi
+
+line=$(grep -h '^scx_utils:clang=' "$out" | tail -1 || true)
+if [ -z "$line" ]; then
+  echo "error: no 'scx_utils:clang=' line in $out" >&2
+  echo "       the build script was cached; touch src/bpf/main.bpf.c and rebuild." >&2
+  exit 1
+fi
+
+# The cflags are the bracketed Rust Vec<String> debug print at the end of the
+# line: ["-g", "-O2", ...]. Pull the quoted strings out of that part only.
+flags=$(printf '%s' "$line" \
+  | sed 's/.*\(\[[^][]*\]\)$/\1/' \
+  | grep -o '"[^"]*"' \
+  | sed 's/^"//; s/"$//')
+
+if [ -z "$flags" ]; then
+  echo "error: could not parse cflags out of: $line" >&2
+  exit 1
+fi
+
+{
+  printf '[\n  {\n'
+  printf '    "directory": "%s",\n' "$root"
+  printf '    "file": "%s/src/bpf/main.bpf.c",\n' "$root"
+  printf '    "arguments": [\n'
+  printf '      "clang",\n'
+  printf '      "-xc",\n'
+  printf '      "-target", "bpf",\n'
+  while IFS= read -r f; do
+    printf '      %s,\n' "$(printf '%s' "$f" | sed 's/\\/\\\\/g; s/"/\\"/g; s/^/"/; s/$/"/')"
+  done <<<"$flags"
+  printf '      "-c",\n'
+  printf '      "%s/src/bpf/main.bpf.c"\n' "$root"
+  printf '    ]\n  }\n]\n'
+} >compile_commands.json
+
+echo "wrote compile_commands.json ($(wc -l <<<"$flags") flags, profile=$profile)"