ci: the dict_hash check counts three hashes, not one distinct value (#172)

The stick-high stage passed when one distinct dict_hash appeared: an
architecture whose boot left no accept file, no LOG: line, no serial log or no
PARITY:V4_SYSTEM line gave nothing, and two that agreed passed for three.

It is now a stage of its own, scripts/nightly.sh dict-hash, which stick-high
runs: one hash from each of amd64, aarch64 and riscv64, all found and one value;
otherwise refused, naming the architectures with none or the values that
differ. NIGHTLY_OUT points the stages at another directory, for the tests.

scripts/test_nightly_dict_hash.sh, written first and seen to fail (6 of 6, the
stage not existing), then 7 cases: agree -- pass; differ, no PARITY line, no
LOG: line, not booted, no serial log, none at all -- refused. Two of them
caught lookups that ended the script silently under set -e; guarded.

Captain Bob, 2026-11-12: "172 then finish alpha.5".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017RzZgrf7V7Zk2iczBXDRbm

scripts/nightly.sh

@@ -13,8 +13,10 @@
 #       time, in that order: scripts/qemu_session.py zuse <arch> -- [zuse@Hera] ok>, `3 4 + .`
 #       -> 7 ok, POST passed -- or stick_zuse amd64 --target qemu-stick-high, the PC stick loaded
 #       above 2 GiB. amd64 keeps the ISO it booted, byte for byte, as build/nightly/StarshipOS.iso.
-#       The last of the four (stick-high) also checks PARITY:V4_SYSTEM's dict_hash is the same
-#       on amd64, aarch64 and riscv64.
+#       The last of the four (stick-high) also runs dict-hash.
+#   scripts/nightly.sh dict-hash
+#       PARITY:V4_SYSTEM's dict_hash from each of the amd64, aarch64 and riscv64 boots: all three
+#       found, and one value (#172 -- it was one distinct value, which two of the three could make).
 #   scripts/nightly.sh test-32
 #       make -C v4 test-32: v4 with 32-bit cells, every test (the acceptance's last part).
 #   scripts/nightly.sh proofs
@@ -69,14 +71,14 @@
 set -euo pipefail
 cd "$(dirname "$0")/.."
 
-OUT=build/nightly
+OUT=${NIGHTLY_OUT:-build/nightly}            # NIGHTLY_OUT: the tests' scratch (scripts/test_nightly_dict_hash.sh)
 DOCS=build/nightly-docs
 LITHOS=$(sed -n 's/^LITHOS_VERSION *?= *//p' kernel/Makefile)
 VERSION=${NIGHTLY_VERSION:-$LITHOS-SNAPSHOT}
 usage() {
     echo "Usage: scripts/nightly.sh accept <amd64|aarch64|riscv64|stick-high> | test-32 | proofs | images" >&2
     echo "                          | publish <URL> | docs | publish-docs <URL> | gitea-release <tag>" >&2
-    echo "                          | protocol [<stage>...] | protocol-report" >&2
+    echo "                          | protocol [<stage>...] | protocol-report | dict-hash" >&2
     echo "  protocol stages: $PROTOCOL_STAGES" >&2
     exit 2
 }
@@ -132,15 +134,26 @@ accept)
     python3 scripts/qemu_session.py $mode $arch $extra --label "nightly-$what" --make "QEMU_DISPLAY=none" \
         | tee "$OUT/accept-$what.txt"
     [ "$what" != amd64 ] || cp build/amd64/kernel/starkernel.iso "$OUT/StarshipOS.iso"
-    if [ "$what" = stick-high ]; then
-        # the three architectures' boots of this run: one dict_hash
-        hashes=$(for a in amd64 aarch64 riscv64; do
-                     log=$(sed -n 's/^LOG: //p' "$OUT/accept-$a.txt")
-                     grep -aoE "PARITY:V4_SYSTEM [^[:cntrl:]]*" "$log" | sed -n 's/.*dict_hash=//p'
-                 done | sort -u)
-        echo "=== nightly: dict_hash on the three: $hashes"
-        [ "$(echo "$hashes" | wc -l)" = 1 ] && [ -n "$hashes" ] \
-            || { echo "nightly: the three architectures do not agree on dict_hash" >&2; exit 1; }
+    [ "$what" != stick-high ] || "$(pwd)/scripts/nightly.sh" dict-hash
+    ;;
+dict-hash)
+    # One dict_hash from each of the three architectures' boots, and the same (#172): an
+    # architecture with no accept file, no LOG: line, no serial log or no PARITY:V4_SYSTEM line
+    # gives no hash, and the check then fails -- two that agree are not three.
+    found=(); missing=()
+    for a in amd64 aarch64 riscv64; do
+        # each lookup may find nothing: under set -e that must be an answer, not the end of the script
+        log=$(sed -n 's/^LOG: //p' "$OUT/accept-$a.txt" 2>/dev/null | head -1 || true)
+        h=$( { [ -n "$log" ] && [ -f "$log" ] && grep -aoE "PARITY:V4_SYSTEM [^[:cntrl:]]*" "$log" | sed -n 's/.*dict_hash=//p' | head -1; } || true)
+        if [ -n "$h" ]; then found+=("$a=$h"); else missing+=("$a"); fi
+    done
+    distinct=$(printf '%s\n' "${found[@]#*=}" | grep . | sort -u || true)
+    echo "=== nightly: dict_hash on the three: ${found[*]:-none}"
+    if [ ${#missing[@]} -gt 0 ]; then
+        echo "nightly: the three architectures do not agree on dict_hash -- none from: ${missing[*]}" >&2; exit 1
+    fi
+    if [ "$(grep -c . <<<"$distinct")" != 1 ]; then
+        echo "nightly: the three architectures do not agree on dict_hash -- $(tr '\n' ' ' <<<"$distinct")" >&2; exit 1
     fi
     ;;
 test-32)