From e410c86f270a013d79639577d82009698b207e8b Mon Sep 17 00:00:00 2001
From: Martin Vogel <martin.vogel.tech@gmail.com>
Date: Mon, 7 Sep 2026 00:32:02 +0200
Subject: [PATCH] fix(pipeline): make the complexity pass independent of worker
 id order

The complexity pass (transitive_loop_depth / recursive) walked Function and
Method nodes in temp-id order and each node's CALLS targets in adjacency
order. Under parallel extraction the temp ids come from one shared atomic
counter, so id order is worker-scheduling order and differs run to run. The
cycle guard flags whichever member of a mutual-recursion cycle the DFS enters
first, so `recursive` flipped between the members of a cycle across otherwise
identical multi-worker runs while the CALLS edge set stayed identical -- a
violation of the MT-byte-identical invariant.

Evidence: on a 66-file Python fixture of equal-sized mutual-recursion cycles
(24 pairs + 6 triangles, adjacent in the size-ordered work queue) a probe saw
3 distinct outputs in 5 runs at 4 workers. The new regression test is RED on
main 5/5 (a 4-worker run diverges from the single-threaded run on the first
cycle every time) and GREEN with this change.

Fix: order the traversal by content only -- seeds sorted by (qualified_name,
file_path, start_line), and each node's CALLS targets sorted the same way
before recursing, through one bump-stack scratch sized to the CALLS edge
count (a single upfront allocation that bails the way the existing calloc
path does). Semantics are unchanged: the DFS entry node of a cycle is the one
flagged, as before; which member that is now depends on the inputs alone,
identically for sequential and parallel indexing. SCC-based marking of every
cycle member is out of scope here.

Test: pipeline_complexity_props_independent_of_worker_order indexes the
fixture once single-threaded and six times with CBM_WORKERS=4 through the
same harness as the sequential/parallel parity test, collects every
Function's complexity props sorted by qualified_name, and asserts all
parallel runs are identical to the sequential run.

Distilled from #1925 with co-author credit.

Verification: build/c/test-runner pipeline complexity extraction (ASan/UBSan)
617 passed, 0 failed; revert-check RED 5/5 on main, GREEN with the fix;
make -f Makefile.cbm lint-ci clean; scripts/check-no-test-skips.sh OK.

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>
Co-authored-by: Zhiyu <zhiyuzhang001@gmail.com>
---
 src/pipeline/pass_complexity.c                | 212 ++++++++++++-----
 .../complexity_pass_cycle_order/p00_a.py      |   6 +
 .../complexity_pass_cycle_order/p00_b.py      |   6 +
 .../complexity_pass_cycle_order/p01_a.py      |   6 +
 .../complexity_pass_cycle_order/p01_b.py      |   6 +
 .../complexity_pass_cycle_order/p02_a.py      |   6 +
 .../complexity_pass_cycle_order/p02_b.py      |   6 +
 .../complexity_pass_cycle_order/p03_a.py      |   6 +
 .../complexity_pass_cycle_order/p03_b.py      |   6 +
 .../complexity_pass_cycle_order/p04_a.py      |   6 +
 .../complexity_pass_cycle_order/p04_b.py      |   6 +
 .../complexity_pass_cycle_order/p05_a.py      |   6 +
 .../complexity_pass_cycle_order/p05_b.py      |   6 +
 .../complexity_pass_cycle_order/p06_a.py      |   6 +
 .../complexity_pass_cycle_order/p06_b.py      |   6 +
 .../complexity_pass_cycle_order/p07_a.py      |   6 +
 .../complexity_pass_cycle_order/p07_b.py      |   6 +
 .../complexity_pass_cycle_order/p08_a.py      |   6 +
 .../complexity_pass_cycle_order/p08_b.py      |   6 +
 .../complexity_pass_cycle_order/p09_a.py      |   6 +
 .../complexity_pass_cycle_order/p09_b.py      |   6 +
 .../complexity_pass_cycle_order/p10_a.py      |   6 +
 .../complexity_pass_cycle_order/p10_b.py      |   6 +
 .../complexity_pass_cycle_order/p11_a.py      |   6 +
 .../complexity_pass_cycle_order/p11_b.py      |   6 +
 .../complexity_pass_cycle_order/p12_a.py      |   6 +
 .../complexity_pass_cycle_order/p12_b.py      |   6 +
 .../complexity_pass_cycle_order/p13_a.py      |   6 +
 .../complexity_pass_cycle_order/p13_b.py      |   6 +
 .../complexity_pass_cycle_order/p14_a.py      |   6 +
 .../complexity_pass_cycle_order/p14_b.py      |   6 +
 .../complexity_pass_cycle_order/p15_a.py      |   6 +
 .../complexity_pass_cycle_order/p15_b.py      |   6 +
 .../complexity_pass_cycle_order/p16_a.py      |   6 +
 .../complexity_pass_cycle_order/p16_b.py      |   6 +
 .../complexity_pass_cycle_order/p17_a.py      |   6 +
 .../complexity_pass_cycle_order/p17_b.py      |   6 +
 .../complexity_pass_cycle_order/p18_a.py      |   6 +
 .../complexity_pass_cycle_order/p18_b.py      |   6 +
 .../complexity_pass_cycle_order/p19_a.py      |   6 +
 .../complexity_pass_cycle_order/p19_b.py      |   6 +
 .../complexity_pass_cycle_order/p20_a.py      |   6 +
 .../complexity_pass_cycle_order/p20_b.py      |   6 +
 .../complexity_pass_cycle_order/p21_a.py      |   6 +
 .../complexity_pass_cycle_order/p21_b.py      |   6 +
 .../complexity_pass_cycle_order/p22_a.py      |   6 +
 .../complexity_pass_cycle_order/p22_b.py      |   6 +
 .../complexity_pass_cycle_order/p23_a.py      |   6 +
 .../complexity_pass_cycle_order/p23_b.py      |   6 +
 .../complexity_pass_cycle_order/t00_x.py      |   6 +
 .../complexity_pass_cycle_order/t00_y.py      |   6 +
 .../complexity_pass_cycle_order/t00_z.py      |   6 +
 .../complexity_pass_cycle_order/t01_x.py      |   6 +
 .../complexity_pass_cycle_order/t01_y.py      |   6 +
 .../complexity_pass_cycle_order/t01_z.py      |   6 +
 .../complexity_pass_cycle_order/t02_x.py      |   6 +
 .../complexity_pass_cycle_order/t02_y.py      |   6 +
 .../complexity_pass_cycle_order/t02_z.py      |   6 +
 .../complexity_pass_cycle_order/t03_x.py      |   6 +
 .../complexity_pass_cycle_order/t03_y.py      |   6 +
 .../complexity_pass_cycle_order/t03_z.py      |   6 +
 .../complexity_pass_cycle_order/t04_x.py      |   6 +
 .../complexity_pass_cycle_order/t04_y.py      |   6 +
 .../complexity_pass_cycle_order/t04_z.py      |   6 +
 .../complexity_pass_cycle_order/t05_x.py      |   6 +
 .../complexity_pass_cycle_order/t05_y.py      |   6 +
 .../complexity_pass_cycle_order/t05_z.py      |   6 +
 tests/test_pipeline.c                         | 221 ++++++++++++++++++
 68 files changed, 773 insertions(+), 56 deletions(-)
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p00_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p00_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p01_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p01_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p02_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p02_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p03_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p03_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p04_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p04_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p05_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p05_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p06_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p06_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p07_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p07_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p08_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p08_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p09_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p09_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p10_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p10_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p11_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p11_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p12_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p12_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p13_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p13_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p14_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p14_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p15_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p15_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p16_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p16_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p17_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p17_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p18_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p18_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p19_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p19_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p20_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p20_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p21_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p21_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p22_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p22_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p23_a.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/p23_b.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t00_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t00_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t00_z.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t01_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t01_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t01_z.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t02_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t02_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t02_z.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t03_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t03_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t03_z.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t04_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t04_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t04_z.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t05_x.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t05_y.py
 create mode 100644 tests/fixtures/complexity_pass_cycle_order/t05_z.py

diff --git a/src/pipeline/pass_complexity.c b/src/pipeline/pass_complexity.c
index 4a3ebf85e..420237b81 100644
--- a/src/pipeline/pass_complexity.c
+++ b/src/pipeline/pass_complexity.c
@@ -99,61 +99,166 @@ static void append_complexity_props(cbm_gbuf_node_t *node, int tld, bool recursi
     node->properties_json = neu;
 }
 
+/* Content-only node order: qualified_name, then file path and start line.
+ * Never the temp id: extract workers draw ids from one shared counter, so id
+ * order is worker-scheduling order and differs run to run. The cycle guard
+ * flags whichever member the DFS ENTERS first, so both the seed order and the
+ * callee order must be a function of the inputs alone, or `recursive` flips
+ * between otherwise identical multi-worker runs. A dangling target (no node
+ * for the id) has no edges of its own, so where it sorts cannot move a flag;
+ * it keys as empty strings. */
+enum { TLD_CMP_LESS = -1, TLD_CMP_GREATER = 1 };
+
+static const char *str_or_empty(const char *s) {
+    return s ? s : "";
+}
+
+static int cmp_node_canonical(const cbm_gbuf_node_t *a, const cbm_gbuf_node_t *b) {
+    int r = strcmp(str_or_empty(a ? a->qualified_name : NULL),
+                   str_or_empty(b ? b->qualified_name : NULL));
+    if (r != 0) {
+        return r;
+    }
+    r = strcmp(str_or_empty(a ? a->file_path : NULL), str_or_empty(b ? b->file_path : NULL));
+    if (r != 0) {
+        return r;
+    }
+    int la = a ? a->start_line : 0;
+    int lb = b ? b->start_line : 0;
+    if (la != lb) {
+        return la < lb ? TLD_CMP_LESS : TLD_CMP_GREATER;
+    }
+    return 0;
+}
+
+static int cmp_seed_canonical(const void *pa, const void *pb) {
+    return cmp_node_canonical(*(const cbm_gbuf_node_t *const *)pa,
+                              *(const cbm_gbuf_node_t *const *)pb);
+}
+
+typedef struct {
+    const cbm_gbuf_node_t *node; /* NULL for a dangling target id */
+    int64_t id;
+} tld_callee_t;
+
+static int cmp_callee_canonical(const void *pa, const void *pb) {
+    return cmp_node_canonical(((const tld_callee_t *)pa)->node, ((const tld_callee_t *)pb)->node);
+}
+
+/* Traversal state. `callees` is one bump stack shared by every DFS frame: a
+ * frame takes its out-degree worth of slots, sorts them, recurses, then
+ * releases them. Nodes on the recursion path are distinct (state 1 blocks
+ * re-entry), so the live slots never exceed the CALLS edge count the stack is
+ * sized for. */
+typedef struct {
+    const cbm_gbuf_t *gb;
+    int64_t maxid;
+    int *loop_depth;
+    int *tld;
+    char *state;
+    bool *recursive;
+    cbm_gbuf_node_t **seeds; /* Function/Method nodes, canonical order */
+    int seed_count;
+    int seed_cap;
+    tld_callee_t *callees;
+    int callee_top;
+    int callee_cap;
+} tld_ctx_t;
+
+static void tld_ctx_free(tld_ctx_t *cx) {
+    free(cx->loop_depth);
+    free(cx->tld);
+    free(cx->state);
+    free(cx->recursive);
+    free(cx->seeds);
+    free(cx->callees);
+}
+
 /* Memoized DFS: tld(id) = loop_depth(id) + max over CALLS-callees of tld(callee).
- * state: 0=unvisited, 1=in-progress (back-edge → cycle), 2=done. */
-static int tld_dfs(const cbm_gbuf_t *gb, int64_t id, const int *loop_depth, int *tld, char *state,
-                   bool *recursive, int64_t maxid, int depth) {
-    if (id < 1 || id > maxid) {
+ * state: 0=unvisited, 1=in-progress (back-edge -> cycle), 2=done. */
+static int tld_dfs(tld_ctx_t *cx, int64_t id, int depth) {
+    if (id < 1 || id > cx->maxid) {
         return 0;
     }
-    if (state[id] == 2) {
-        return tld[id];
+    if (cx->state[id] == 2) {
+        return cx->tld[id];
     }
-    if (state[id] == 1) {
-        recursive[id] = true; /* back edge → call-graph cycle */
+    if (cx->state[id] == 1) {
+        cx->recursive[id] = true; /* back edge -> call-graph cycle */
         return 0;
     }
     if (depth > CBM_TLD_MAX_DEPTH) {
-        return loop_depth[id];
+        return cx->loop_depth[id];
     }
-    state[id] = 1;
-    int best = 0;
     const cbm_gbuf_edge_t **edges = NULL;
     int ne = 0;
-    cbm_gbuf_find_edges_by_source_type(gb, id, "CALLS", &edges, &ne);
+    cbm_gbuf_find_edges_by_source_type(cx->gb, id, "CALLS", &edges, &ne);
+    if (ne > cx->callee_cap - cx->callee_top) {
+        return cx->loop_depth[id]; /* unreachable by construction; same as the depth cap */
+    }
+    cx->state[id] = 1;
+    tld_callee_t *callees = cx->callees + cx->callee_top;
+    int nc = 0;
     for (int i = 0; i < ne; i++) {
         int64_t c = edges[i]->target_id;
         if (c == id) {
-            recursive[id] = true; /* direct self-recursion */
+            cx->recursive[id] = true; /* direct self-recursion */
             continue;
         }
-        int ct = tld_dfs(gb, c, loop_depth, tld, state, recursive, maxid, depth + 1);
+        callees[nc].id = c;
+        callees[nc].node = cbm_gbuf_find_by_id(cx->gb, c);
+        nc++;
+    }
+    cx->callee_top += nc;
+    qsort(callees, (size_t)nc, sizeof(*callees), cmp_callee_canonical);
+    int best = 0;
+    for (int i = 0; i < nc; i++) {
+        int ct = tld_dfs(cx, callees[i].id, depth + 1);
         if (ct > best) {
             best = ct;
         }
     }
-    tld[id] = loop_depth[id] + best;
-    state[id] = 2;
-    return tld[id];
+    cx->callee_top -= nc;
+    cx->tld[id] = cx->loop_depth[id] + best;
+    cx->state[id] = 2;
+    return cx->tld[id];
 }
 
-/* Seed each Function/Method node's loop_depth and self_recursive flag, and
- * remember the node pointer for write-back. The self_recursive seed (set at
- * extraction) feeds the final recursive flag; tld_dfs additionally ORs in
- * mutual recursion discovered as a call-graph cycle. */
-static void seed_loop_depths(const cbm_gbuf_t *gb, const char *label, int *loop_depth,
-                             bool *recursive, cbm_gbuf_node_t **nptr, int64_t maxid) {
+static int label_count(const cbm_gbuf_t *gb, const char *label) {
     const cbm_gbuf_node_t **nodes = NULL;
     int count = 0;
     if (cbm_gbuf_find_by_label(gb, label, &nodes, &count) != 0) {
+        return 0;
+    }
+    return count;
+}
+
+static int calls_edge_count(const cbm_gbuf_t *gb) {
+    const cbm_gbuf_edge_t **edges = NULL;
+    int count = 0;
+    if (cbm_gbuf_find_edges_by_type(gb, "CALLS", &edges, &count) != 0) {
+        return 0;
+    }
+    return count;
+}
+
+/* Seed each Function/Method node's loop_depth and self_recursive flag, and
+ * collect the node as a traversal seed (also the write-back target). The
+ * self_recursive seed (set at extraction) feeds the final recursive flag;
+ * tld_dfs additionally ORs in mutual recursion discovered as a call-graph
+ * cycle. */
+static void seed_loop_depths(tld_ctx_t *cx, const char *label) {
+    const cbm_gbuf_node_t **nodes = NULL;
+    int count = 0;
+    if (cbm_gbuf_find_by_label(cx->gb, label, &nodes, &count) != 0) {
         return;
     }
-    for (int i = 0; i < count; i++) {
+    for (int i = 0; i < count && cx->seed_count < cx->seed_cap; i++) {
         const cbm_gbuf_node_t *n = nodes[i];
-        if (n->id >= 1 && n->id <= maxid) {
-            loop_depth[n->id] = json_get_int(n->properties_json, "loop_depth", 0);
-            recursive[n->id] = json_get_bool(n->properties_json, "self_recursive");
-            nptr[n->id] = (cbm_gbuf_node_t *)n;
+        if (n->id >= 1 && n->id <= cx->maxid) {
+            cx->loop_depth[n->id] = json_get_int(n->properties_json, "loop_depth", 0);
+            cx->recursive[n->id] = json_get_bool(n->properties_json, "self_recursive");
+            cx->seeds[cx->seed_count++] = (cbm_gbuf_node_t *)n;
         }
     }
 }
@@ -168,40 +273,35 @@ void cbm_pipeline_pass_complexity(cbm_pipeline_ctx_t *ctx) {
         return;
     }
     size_t sz = (size_t)maxid + 1;
-    int *loop_depth = calloc(sz, sizeof(int));
-    int *tld = calloc(sz, sizeof(int));
-    char *state = calloc(sz, sizeof(char));
-    bool *recursive = calloc(sz, sizeof(bool));
-    cbm_gbuf_node_t **nptr = calloc(sz, sizeof(cbm_gbuf_node_t *));
-    if (!loop_depth || !tld || !state || !recursive || !nptr) {
-        free(loop_depth);
-        free(tld);
-        free(state);
-        free(recursive);
-        free(nptr);
+    tld_ctx_t cx = {0};
+    cx.gb = gb;
+    cx.maxid = maxid;
+    cx.seed_cap = label_count(gb, "Function") + label_count(gb, "Method");
+    cx.callee_cap = calls_edge_count(gb);
+    cx.loop_depth = calloc(sz, sizeof(int));
+    cx.tld = calloc(sz, sizeof(int));
+    cx.state = calloc(sz, sizeof(char));
+    cx.recursive = calloc(sz, sizeof(bool));
+    cx.seeds = calloc((size_t)cx.seed_cap + 1, sizeof(cbm_gbuf_node_t *));
+    cx.callees = calloc((size_t)cx.callee_cap + 1, sizeof(tld_callee_t));
+    if (!cx.loop_depth || !cx.tld || !cx.state || !cx.recursive || !cx.seeds || !cx.callees) {
+        tld_ctx_free(&cx);
         return;
     }
 
-    seed_loop_depths(gb, "Function", loop_depth, recursive, nptr, maxid);
-    seed_loop_depths(gb, "Method", loop_depth, recursive, nptr, maxid);
+    seed_loop_depths(&cx, "Function");
+    seed_loop_depths(&cx, "Method");
+    qsort(cx.seeds, (size_t)cx.seed_count, sizeof(*cx.seeds), cmp_seed_canonical);
 
-    int updated = 0;
-    for (int64_t id = 1; id <= maxid; id++) {
-        if (!nptr[id]) {
-            continue; /* only Function/Method nodes */
-        }
-        if (state[id] != 2) {
-            tld_dfs(gb, id, loop_depth, tld, state, recursive, maxid, 0);
+    for (int i = 0; i < cx.seed_count; i++) {
+        cbm_gbuf_node_t *n = cx.seeds[i];
+        if (cx.state[n->id] != 2) {
+            tld_dfs(&cx, n->id, 0);
         }
-        append_complexity_props(nptr[id], tld[id], recursive[id]);
-        updated++;
+        append_complexity_props(n, cx.tld[n->id], cx.recursive[n->id]);
     }
 
-    cbm_log_info("pass.complexity", "functions", itoa_cx(updated));
+    cbm_log_info("pass.complexity", "functions", itoa_cx(cx.seed_count));
 
-    free(loop_depth);
-    free(tld);
-    free(state);
-    free(recursive);
-    free(nptr);
+    tld_ctx_free(&cx);
 }
diff --git a/tests/fixtures/complexity_pass_cycle_order/p00_a.py b/tests/fixtures/complexity_pass_cycle_order/p00_a.py
new file mode 100644
index 000000000..ff8d38616
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p00_a.py
@@ -0,0 +1,6 @@
+from p00_b import pair00_b
+
+def pair00_a(n):
+    for _ in range(n):
+        pass
+    return pair00_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p00_b.py b/tests/fixtures/complexity_pass_cycle_order/p00_b.py
new file mode 100644
index 000000000..5d2939ce9
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p00_b.py
@@ -0,0 +1,6 @@
+from p00_a import pair00_a
+
+def pair00_b(n):
+    if n <= 0:
+        return 0
+    return pair00_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p01_a.py b/tests/fixtures/complexity_pass_cycle_order/p01_a.py
new file mode 100644
index 000000000..b602a8192
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p01_a.py
@@ -0,0 +1,6 @@
+from p01_b import pair01_b
+
+def pair01_a(n):
+    for _ in range(n):
+        pass
+    return pair01_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p01_b.py b/tests/fixtures/complexity_pass_cycle_order/p01_b.py
new file mode 100644
index 000000000..8ef871ebd
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p01_b.py
@@ -0,0 +1,6 @@
+from p01_a import pair01_a
+
+def pair01_b(n):
+    if n <= 0:
+        return 0
+    return pair01_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p02_a.py b/tests/fixtures/complexity_pass_cycle_order/p02_a.py
new file mode 100644
index 000000000..f77ffe62a
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p02_a.py
@@ -0,0 +1,6 @@
+from p02_b import pair02_b
+
+def pair02_a(n):
+    for _ in range(n):
+        pass
+    return pair02_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p02_b.py b/tests/fixtures/complexity_pass_cycle_order/p02_b.py
new file mode 100644
index 000000000..a7e5baf30
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p02_b.py
@@ -0,0 +1,6 @@
+from p02_a import pair02_a
+
+def pair02_b(n):
+    if n <= 0:
+        return 0
+    return pair02_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p03_a.py b/tests/fixtures/complexity_pass_cycle_order/p03_a.py
new file mode 100644
index 000000000..c59dad576
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p03_a.py
@@ -0,0 +1,6 @@
+from p03_b import pair03_b
+
+def pair03_a(n):
+    for _ in range(n):
+        pass
+    return pair03_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p03_b.py b/tests/fixtures/complexity_pass_cycle_order/p03_b.py
new file mode 100644
index 000000000..90f807bcd
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p03_b.py
@@ -0,0 +1,6 @@
+from p03_a import pair03_a
+
+def pair03_b(n):
+    if n <= 0:
+        return 0
+    return pair03_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p04_a.py b/tests/fixtures/complexity_pass_cycle_order/p04_a.py
new file mode 100644
index 000000000..89a1385b0
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p04_a.py
@@ -0,0 +1,6 @@
+from p04_b import pair04_b
+
+def pair04_a(n):
+    for _ in range(n):
+        pass
+    return pair04_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p04_b.py b/tests/fixtures/complexity_pass_cycle_order/p04_b.py
new file mode 100644
index 000000000..a333f1079
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p04_b.py
@@ -0,0 +1,6 @@
+from p04_a import pair04_a
+
+def pair04_b(n):
+    if n <= 0:
+        return 0
+    return pair04_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p05_a.py b/tests/fixtures/complexity_pass_cycle_order/p05_a.py
new file mode 100644
index 000000000..356bc4259
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p05_a.py
@@ -0,0 +1,6 @@
+from p05_b import pair05_b
+
+def pair05_a(n):
+    for _ in range(n):
+        pass
+    return pair05_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p05_b.py b/tests/fixtures/complexity_pass_cycle_order/p05_b.py
new file mode 100644
index 000000000..b51770ba7
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p05_b.py
@@ -0,0 +1,6 @@
+from p05_a import pair05_a
+
+def pair05_b(n):
+    if n <= 0:
+        return 0
+    return pair05_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p06_a.py b/tests/fixtures/complexity_pass_cycle_order/p06_a.py
new file mode 100644
index 000000000..c01b33466
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p06_a.py
@@ -0,0 +1,6 @@
+from p06_b import pair06_b
+
+def pair06_a(n):
+    for _ in range(n):
+        pass
+    return pair06_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p06_b.py b/tests/fixtures/complexity_pass_cycle_order/p06_b.py
new file mode 100644
index 000000000..d13628e36
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p06_b.py
@@ -0,0 +1,6 @@
+from p06_a import pair06_a
+
+def pair06_b(n):
+    if n <= 0:
+        return 0
+    return pair06_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p07_a.py b/tests/fixtures/complexity_pass_cycle_order/p07_a.py
new file mode 100644
index 000000000..9bf317024
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p07_a.py
@@ -0,0 +1,6 @@
+from p07_b import pair07_b
+
+def pair07_a(n):
+    for _ in range(n):
+        pass
+    return pair07_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p07_b.py b/tests/fixtures/complexity_pass_cycle_order/p07_b.py
new file mode 100644
index 000000000..b3478c704
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p07_b.py
@@ -0,0 +1,6 @@
+from p07_a import pair07_a
+
+def pair07_b(n):
+    if n <= 0:
+        return 0
+    return pair07_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p08_a.py b/tests/fixtures/complexity_pass_cycle_order/p08_a.py
new file mode 100644
index 000000000..146b0886e
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p08_a.py
@@ -0,0 +1,6 @@
+from p08_b import pair08_b
+
+def pair08_a(n):
+    for _ in range(n):
+        pass
+    return pair08_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p08_b.py b/tests/fixtures/complexity_pass_cycle_order/p08_b.py
new file mode 100644
index 000000000..c97c509a0
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p08_b.py
@@ -0,0 +1,6 @@
+from p08_a import pair08_a
+
+def pair08_b(n):
+    if n <= 0:
+        return 0
+    return pair08_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p09_a.py b/tests/fixtures/complexity_pass_cycle_order/p09_a.py
new file mode 100644
index 000000000..e03e52d92
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p09_a.py
@@ -0,0 +1,6 @@
+from p09_b import pair09_b
+
+def pair09_a(n):
+    for _ in range(n):
+        pass
+    return pair09_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p09_b.py b/tests/fixtures/complexity_pass_cycle_order/p09_b.py
new file mode 100644
index 000000000..4cf1149bd
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p09_b.py
@@ -0,0 +1,6 @@
+from p09_a import pair09_a
+
+def pair09_b(n):
+    if n <= 0:
+        return 0
+    return pair09_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p10_a.py b/tests/fixtures/complexity_pass_cycle_order/p10_a.py
new file mode 100644
index 000000000..7c8e3efd5
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p10_a.py
@@ -0,0 +1,6 @@
+from p10_b import pair10_b
+
+def pair10_a(n):
+    for _ in range(n):
+        pass
+    return pair10_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p10_b.py b/tests/fixtures/complexity_pass_cycle_order/p10_b.py
new file mode 100644
index 000000000..ec23c5c37
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p10_b.py
@@ -0,0 +1,6 @@
+from p10_a import pair10_a
+
+def pair10_b(n):
+    if n <= 0:
+        return 0
+    return pair10_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p11_a.py b/tests/fixtures/complexity_pass_cycle_order/p11_a.py
new file mode 100644
index 000000000..b12fab327
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p11_a.py
@@ -0,0 +1,6 @@
+from p11_b import pair11_b
+
+def pair11_a(n):
+    for _ in range(n):
+        pass
+    return pair11_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p11_b.py b/tests/fixtures/complexity_pass_cycle_order/p11_b.py
new file mode 100644
index 000000000..1cb4f26e5
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p11_b.py
@@ -0,0 +1,6 @@
+from p11_a import pair11_a
+
+def pair11_b(n):
+    if n <= 0:
+        return 0
+    return pair11_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p12_a.py b/tests/fixtures/complexity_pass_cycle_order/p12_a.py
new file mode 100644
index 000000000..3cfdade22
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p12_a.py
@@ -0,0 +1,6 @@
+from p12_b import pair12_b
+
+def pair12_a(n):
+    for _ in range(n):
+        pass
+    return pair12_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p12_b.py b/tests/fixtures/complexity_pass_cycle_order/p12_b.py
new file mode 100644
index 000000000..43e53aa04
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p12_b.py
@@ -0,0 +1,6 @@
+from p12_a import pair12_a
+
+def pair12_b(n):
+    if n <= 0:
+        return 0
+    return pair12_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p13_a.py b/tests/fixtures/complexity_pass_cycle_order/p13_a.py
new file mode 100644
index 000000000..7acb11ad7
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p13_a.py
@@ -0,0 +1,6 @@
+from p13_b import pair13_b
+
+def pair13_a(n):
+    for _ in range(n):
+        pass
+    return pair13_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p13_b.py b/tests/fixtures/complexity_pass_cycle_order/p13_b.py
new file mode 100644
index 000000000..f222cb03b
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p13_b.py
@@ -0,0 +1,6 @@
+from p13_a import pair13_a
+
+def pair13_b(n):
+    if n <= 0:
+        return 0
+    return pair13_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p14_a.py b/tests/fixtures/complexity_pass_cycle_order/p14_a.py
new file mode 100644
index 000000000..46c15ab00
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p14_a.py
@@ -0,0 +1,6 @@
+from p14_b import pair14_b
+
+def pair14_a(n):
+    for _ in range(n):
+        pass
+    return pair14_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p14_b.py b/tests/fixtures/complexity_pass_cycle_order/p14_b.py
new file mode 100644
index 000000000..18e458f54
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p14_b.py
@@ -0,0 +1,6 @@
+from p14_a import pair14_a
+
+def pair14_b(n):
+    if n <= 0:
+        return 0
+    return pair14_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p15_a.py b/tests/fixtures/complexity_pass_cycle_order/p15_a.py
new file mode 100644
index 000000000..542e43e58
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p15_a.py
@@ -0,0 +1,6 @@
+from p15_b import pair15_b
+
+def pair15_a(n):
+    for _ in range(n):
+        pass
+    return pair15_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p15_b.py b/tests/fixtures/complexity_pass_cycle_order/p15_b.py
new file mode 100644
index 000000000..e79bbf276
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p15_b.py
@@ -0,0 +1,6 @@
+from p15_a import pair15_a
+
+def pair15_b(n):
+    if n <= 0:
+        return 0
+    return pair15_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p16_a.py b/tests/fixtures/complexity_pass_cycle_order/p16_a.py
new file mode 100644
index 000000000..f981a15de
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p16_a.py
@@ -0,0 +1,6 @@
+from p16_b import pair16_b
+
+def pair16_a(n):
+    for _ in range(n):
+        pass
+    return pair16_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p16_b.py b/tests/fixtures/complexity_pass_cycle_order/p16_b.py
new file mode 100644
index 000000000..2585aba96
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p16_b.py
@@ -0,0 +1,6 @@
+from p16_a import pair16_a
+
+def pair16_b(n):
+    if n <= 0:
+        return 0
+    return pair16_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p17_a.py b/tests/fixtures/complexity_pass_cycle_order/p17_a.py
new file mode 100644
index 000000000..57c3cd1e5
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p17_a.py
@@ -0,0 +1,6 @@
+from p17_b import pair17_b
+
+def pair17_a(n):
+    for _ in range(n):
+        pass
+    return pair17_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p17_b.py b/tests/fixtures/complexity_pass_cycle_order/p17_b.py
new file mode 100644
index 000000000..94392a7ff
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p17_b.py
@@ -0,0 +1,6 @@
+from p17_a import pair17_a
+
+def pair17_b(n):
+    if n <= 0:
+        return 0
+    return pair17_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p18_a.py b/tests/fixtures/complexity_pass_cycle_order/p18_a.py
new file mode 100644
index 000000000..55ef68989
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p18_a.py
@@ -0,0 +1,6 @@
+from p18_b import pair18_b
+
+def pair18_a(n):
+    for _ in range(n):
+        pass
+    return pair18_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p18_b.py b/tests/fixtures/complexity_pass_cycle_order/p18_b.py
new file mode 100644
index 000000000..ae2f67de9
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p18_b.py
@@ -0,0 +1,6 @@
+from p18_a import pair18_a
+
+def pair18_b(n):
+    if n <= 0:
+        return 0
+    return pair18_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p19_a.py b/tests/fixtures/complexity_pass_cycle_order/p19_a.py
new file mode 100644
index 000000000..3641aa150
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p19_a.py
@@ -0,0 +1,6 @@
+from p19_b import pair19_b
+
+def pair19_a(n):
+    for _ in range(n):
+        pass
+    return pair19_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p19_b.py b/tests/fixtures/complexity_pass_cycle_order/p19_b.py
new file mode 100644
index 000000000..27b3cb8d0
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p19_b.py
@@ -0,0 +1,6 @@
+from p19_a import pair19_a
+
+def pair19_b(n):
+    if n <= 0:
+        return 0
+    return pair19_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p20_a.py b/tests/fixtures/complexity_pass_cycle_order/p20_a.py
new file mode 100644
index 000000000..2097d17e3
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p20_a.py
@@ -0,0 +1,6 @@
+from p20_b import pair20_b
+
+def pair20_a(n):
+    for _ in range(n):
+        pass
+    return pair20_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p20_b.py b/tests/fixtures/complexity_pass_cycle_order/p20_b.py
new file mode 100644
index 000000000..fc0535bdf
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p20_b.py
@@ -0,0 +1,6 @@
+from p20_a import pair20_a
+
+def pair20_b(n):
+    if n <= 0:
+        return 0
+    return pair20_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p21_a.py b/tests/fixtures/complexity_pass_cycle_order/p21_a.py
new file mode 100644
index 000000000..47991e4c8
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p21_a.py
@@ -0,0 +1,6 @@
+from p21_b import pair21_b
+
+def pair21_a(n):
+    for _ in range(n):
+        pass
+    return pair21_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p21_b.py b/tests/fixtures/complexity_pass_cycle_order/p21_b.py
new file mode 100644
index 000000000..3fb5ae276
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p21_b.py
@@ -0,0 +1,6 @@
+from p21_a import pair21_a
+
+def pair21_b(n):
+    if n <= 0:
+        return 0
+    return pair21_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p22_a.py b/tests/fixtures/complexity_pass_cycle_order/p22_a.py
new file mode 100644
index 000000000..e0801bcde
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p22_a.py
@@ -0,0 +1,6 @@
+from p22_b import pair22_b
+
+def pair22_a(n):
+    for _ in range(n):
+        pass
+    return pair22_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p22_b.py b/tests/fixtures/complexity_pass_cycle_order/p22_b.py
new file mode 100644
index 000000000..f6f47b3e2
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p22_b.py
@@ -0,0 +1,6 @@
+from p22_a import pair22_a
+
+def pair22_b(n):
+    if n <= 0:
+        return 0
+    return pair22_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p23_a.py b/tests/fixtures/complexity_pass_cycle_order/p23_a.py
new file mode 100644
index 000000000..52a3b8c73
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p23_a.py
@@ -0,0 +1,6 @@
+from p23_b import pair23_b
+
+def pair23_a(n):
+    for _ in range(n):
+        pass
+    return pair23_b(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/p23_b.py b/tests/fixtures/complexity_pass_cycle_order/p23_b.py
new file mode 100644
index 000000000..c895395b7
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/p23_b.py
@@ -0,0 +1,6 @@
+from p23_a import pair23_a
+
+def pair23_b(n):
+    if n <= 0:
+        return 0
+    return pair23_a(n)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t00_x.py b/tests/fixtures/complexity_pass_cycle_order/t00_x.py
new file mode 100644
index 000000000..a67153c33
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t00_x.py
@@ -0,0 +1,6 @@
+from t00_y import tri00_y
+
+def tri00_x(n):
+    for _ in range(n):
+        pass
+    return tri00_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t00_y.py b/tests/fixtures/complexity_pass_cycle_order/t00_y.py
new file mode 100644
index 000000000..01b6464bd
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t00_y.py
@@ -0,0 +1,6 @@
+from t00_z import tri00_z
+
+def tri00_y(n):
+    for _ in range(n):
+        pass
+    return tri00_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t00_z.py b/tests/fixtures/complexity_pass_cycle_order/t00_z.py
new file mode 100644
index 000000000..5584e2b49
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t00_z.py
@@ -0,0 +1,6 @@
+from t00_x import tri00_x
+
+def tri00_z(n):
+    for _ in range(n):
+        pass
+    return tri00_x(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t01_x.py b/tests/fixtures/complexity_pass_cycle_order/t01_x.py
new file mode 100644
index 000000000..c4a2a8cf5
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t01_x.py
@@ -0,0 +1,6 @@
+from t01_y import tri01_y
+
+def tri01_x(n):
+    for _ in range(n):
+        pass
+    return tri01_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t01_y.py b/tests/fixtures/complexity_pass_cycle_order/t01_y.py
new file mode 100644
index 000000000..e1f0361a9
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t01_y.py
@@ -0,0 +1,6 @@
+from t01_z import tri01_z
+
+def tri01_y(n):
+    for _ in range(n):
+        pass
+    return tri01_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t01_z.py b/tests/fixtures/complexity_pass_cycle_order/t01_z.py
new file mode 100644
index 000000000..7998c851e
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t01_z.py
@@ -0,0 +1,6 @@
+from t01_x import tri01_x
+
+def tri01_z(n):
+    for _ in range(n):
+        pass
+    return tri01_x(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t02_x.py b/tests/fixtures/complexity_pass_cycle_order/t02_x.py
new file mode 100644
index 000000000..897202553
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t02_x.py
@@ -0,0 +1,6 @@
+from t02_y import tri02_y
+
+def tri02_x(n):
+    for _ in range(n):
+        pass
+    return tri02_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t02_y.py b/tests/fixtures/complexity_pass_cycle_order/t02_y.py
new file mode 100644
index 000000000..e6f78bc59
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t02_y.py
@@ -0,0 +1,6 @@
+from t02_z import tri02_z
+
+def tri02_y(n):
+    for _ in range(n):
+        pass
+    return tri02_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t02_z.py b/tests/fixtures/complexity_pass_cycle_order/t02_z.py
new file mode 100644
index 000000000..d056cf849
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t02_z.py
@@ -0,0 +1,6 @@
+from t02_x import tri02_x
+
+def tri02_z(n):
+    for _ in range(n):
+        pass
+    return tri02_x(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t03_x.py b/tests/fixtures/complexity_pass_cycle_order/t03_x.py
new file mode 100644
index 000000000..deb0b989e
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t03_x.py
@@ -0,0 +1,6 @@
+from t03_y import tri03_y
+
+def tri03_x(n):
+    for _ in range(n):
+        pass
+    return tri03_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t03_y.py b/tests/fixtures/complexity_pass_cycle_order/t03_y.py
new file mode 100644
index 000000000..de3a290af
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t03_y.py
@@ -0,0 +1,6 @@
+from t03_z import tri03_z
+
+def tri03_y(n):
+    for _ in range(n):
+        pass
+    return tri03_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t03_z.py b/tests/fixtures/complexity_pass_cycle_order/t03_z.py
new file mode 100644
index 000000000..0bfda4c58
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t03_z.py
@@ -0,0 +1,6 @@
+from t03_x import tri03_x
+
+def tri03_z(n):
+    for _ in range(n):
+        pass
+    return tri03_x(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t04_x.py b/tests/fixtures/complexity_pass_cycle_order/t04_x.py
new file mode 100644
index 000000000..51d9bf949
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t04_x.py
@@ -0,0 +1,6 @@
+from t04_y import tri04_y
+
+def tri04_x(n):
+    for _ in range(n):
+        pass
+    return tri04_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t04_y.py b/tests/fixtures/complexity_pass_cycle_order/t04_y.py
new file mode 100644
index 000000000..f785837d1
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t04_y.py
@@ -0,0 +1,6 @@
+from t04_z import tri04_z
+
+def tri04_y(n):
+    for _ in range(n):
+        pass
+    return tri04_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t04_z.py b/tests/fixtures/complexity_pass_cycle_order/t04_z.py
new file mode 100644
index 000000000..f029c5fc3
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t04_z.py
@@ -0,0 +1,6 @@
+from t04_x import tri04_x
+
+def tri04_z(n):
+    for _ in range(n):
+        pass
+    return tri04_x(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t05_x.py b/tests/fixtures/complexity_pass_cycle_order/t05_x.py
new file mode 100644
index 000000000..d91398497
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t05_x.py
@@ -0,0 +1,6 @@
+from t05_y import tri05_y
+
+def tri05_x(n):
+    for _ in range(n):
+        pass
+    return tri05_y(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t05_y.py b/tests/fixtures/complexity_pass_cycle_order/t05_y.py
new file mode 100644
index 000000000..d4d95e83f
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t05_y.py
@@ -0,0 +1,6 @@
+from t05_z import tri05_z
+
+def tri05_y(n):
+    for _ in range(n):
+        pass
+    return tri05_z(n - 1)
diff --git a/tests/fixtures/complexity_pass_cycle_order/t05_z.py b/tests/fixtures/complexity_pass_cycle_order/t05_z.py
new file mode 100644
index 000000000..b865893ad
--- /dev/null
+++ b/tests/fixtures/complexity_pass_cycle_order/t05_z.py
@@ -0,0 +1,6 @@
+from t05_x import tri05_x
+
+def tri05_z(n):
+    for _ in range(n):
+        pass
+    return tri05_x(n - 1)
diff --git a/tests/test_pipeline.c b/tests/test_pipeline.c
index cf40dd57a..ab239eeef 100644
--- a/tests/test_pipeline.c
+++ b/tests/test_pipeline.c
@@ -2066,6 +2066,226 @@ TEST(pipeline_call_reference_sequential_parallel_edge_set_parity) {
     PASS();
 }
 
+/* Reproduce-first for the multi-worker determinism gap distilled from #1925:
+ * the complexity pass walked Function/Method nodes and their CALLS targets in
+ * temp-id order. Extract workers draw ids from one shared counter, so that
+ * order is worker-scheduling order, and the cycle guard flags whichever member
+ * of a mutual-recursion cycle the DFS enters first. Run to run, `recursive`
+ * therefore flipped between the members of a cycle while the CALLS edge set
+ * stayed identical -- a violation of the MT-byte-identical invariant. The
+ * fixture holds 24 two-member and 6 three-member cycles, one function per
+ * file, whose members are equal-sized (adjacent in the size-ordered work
+ * queue), which is what makes the flip likely. The
+ * fixture exceeds MIN_FILES_FOR_PARALLEL; CBM_INDEX_SINGLE_THREAD forces the
+ * reference run through the sequential path and CBM_WORKERS forces the
+ * repeated runs through pass_parallel.c, exactly like the parity test above.
+ * Every multi-worker run must match the sequential one byte for byte. */
+enum { CX_ORDER_MT_RUNS = 6, CX_ORDER_LINE_MAX = 512 };
+
+static const char *cx_order_fixture_dir(void) {
+    return "tests/fixtures/complexity_pass_cycle_order";
+}
+
+/* Copy the regular files of a flat fixture directory into dst_dir. Returns the
+ * number of files copied, or -1 when one could not be read whole. */
+static int cx_order_copy_fixture(const char *src_dir, const char *dst_dir) {
+    cbm_dir_t *d = cbm_opendir(src_dir);
+    if (!d) {
+        return -1;
+    }
+    int copied = 0;
+    cbm_dirent_t *entry;
+    while ((entry = cbm_readdir(d)) != NULL) {
+        if (entry->name[0] == '.' || entry->is_dir) {
+            continue;
+        }
+        char src[CBM_SZ_1K];
+        snprintf(src, sizeof(src), "%s/%s", src_dir, entry->name);
+        FILE *in = cbm_fopen(src, "rb");
+        if (!in) {
+            copied = -1;
+            break;
+        }
+        char buf[CBM_SZ_4K];
+        size_t n = fread(buf, 1, sizeof(buf) - 1, in);
+        fclose(in);
+        if (n == sizeof(buf) - 1) {
+            copied = -1; /* fixture files are tiny; a full buffer means truncation */
+            break;
+        }
+        buf[n] = '\0';
+        write_temp_file(dst_dir, entry->name, buf);
+        copied++;
+    }
+    cbm_closedir(d);
+    return copied;
+}
+
+static int cx_order_cmp_node_qn(const void *pa, const void *pb) {
+    const cbm_node_t *a = *(const cbm_node_t *const *)pa;
+    const cbm_node_t *b = *(const cbm_node_t *const *)pb;
+    return strcmp(a->qualified_name ? a->qualified_name : "",
+                  b->qualified_name ? b->qualified_name : "");
+}
+
+/* One line per Function in qualified-name order: "<qn> <tld> <recursive>".
+ * Sorting by name keeps DB ids and row order out of the comparison. Returns a
+ * heap string, or NULL when the store cannot be read. */
+static char *cx_order_signature(const char *db_path, const char *project, int *func_count) {
+    cbm_store_t *s = cbm_store_open_path(db_path);
+    if (!s) {
+        return NULL;
+    }
+    cbm_node_t *funcs = NULL;
+    int count = 0;
+    if (cbm_store_find_nodes_by_label(s, project, "Function", &funcs, &count) != CBM_STORE_OK) {
+        cbm_store_close(s);
+        return NULL;
+    }
+    const cbm_node_t **sorted = calloc((size_t)count + 1, sizeof(*sorted));
+    char *sig = calloc((size_t)count + 1, CX_ORDER_LINE_MAX);
+    if (sorted && sig) {
+        for (int i = 0; i < count; i++) {
+            sorted[i] = &funcs[i];
+        }
+        qsort(sorted, (size_t)count, sizeof(*sorted), cx_order_cmp_node_qn);
+        size_t used = 0;
+        for (int i = 0; i < count; i++) {
+            const char *props = sorted[i]->properties_json ? sorted[i]->properties_json : "{}";
+            const char *tld = strstr(props, "\"transitive_loop_depth\":");
+            const char *rec = strstr(props, "\"recursive\":");
+            int w = snprintf(sig + used, CX_ORDER_LINE_MAX, "%s %.*s %.*s\n",
+                             sorted[i]->qualified_name ? sorted[i]->qualified_name : "",
+                             tld ? (int)strcspn(tld, ",}") : 0, tld ? tld : "",
+                             rec ? (int)strcspn(rec, ",}") : 0, rec ? rec : "");
+            if (w < 0) {
+                w = 0;
+            } else if (w >= CX_ORDER_LINE_MAX) {
+                w = CX_ORDER_LINE_MAX - 1;
+            }
+            used += (size_t)w;
+        }
+    } else {
+        free(sig);
+        sig = NULL;
+    }
+    free(sorted);
+    cbm_store_free_nodes(funcs, count);
+    cbm_store_close(s);
+    *func_count = count;
+    return sig;
+}
+
+/* First line of `got` that differs from `want`, copied into out (for the
+ * failure diagnostic). Returns false when the strings are identical. */
+static bool cx_order_first_diff(const char *want, const char *got, char *out, size_t cap) {
+    if (strcmp(want, got) == 0) {
+        return false;
+    }
+    while (*want && *got) {
+        size_t lw = strcspn(want, "\n");
+        size_t lg = strcspn(got, "\n");
+        if (lw != lg || memcmp(want, got, lw) != 0) {
+            snprintf(out, cap, "want '%.*s' got '%.*s'", (int)lw, want, (int)lg, got);
+            return true;
+        }
+        want += lw + (want[lw] == '\n');
+        got += lg + (got[lg] == '\n');
+    }
+    snprintf(out, cap, "line count differs");
+    return true;
+}
+
+TEST(pipeline_complexity_props_independent_of_worker_order) {
+    char tmp[256];
+    snprintf(tmp, sizeof(tmp), "/tmp/cbm_cx_order_XXXXXX");
+    if (!cbm_mkdtemp(tmp)) {
+        FAIL("tmpdir");
+    }
+    int copied = cx_order_copy_fixture(cx_order_fixture_dir(), tmp);
+    if (copied <= 0) {
+        th_rmtree(tmp);
+        FAIL("fixture copy");
+    }
+
+    char *old_workers = getenv("CBM_WORKERS");
+    char *saved_workers = old_workers ? strdup(old_workers) : NULL;
+    char *old_single = getenv("CBM_INDEX_SINGLE_THREAD");
+    char *saved_single = old_single ? strdup(old_single) : NULL;
+
+    cbm_setenv("CBM_INDEX_SINGLE_THREAD", "1", 1);
+    char db_path[512];
+    snprintf(db_path, sizeof(db_path), "%s/cx_sequential.db", tmp);
+    cbm_pipeline_t *sequential = cbm_pipeline_new(tmp, db_path, CBM_MODE_FULL);
+    int sequential_rc = sequential ? cbm_pipeline_run(sequential) : -1;
+    int sequential_funcs = 0;
+    char *sequential_sig = NULL;
+    if (sequential && sequential_rc == 0) {
+        sequential_sig =
+            cx_order_signature(db_path, cbm_pipeline_project_name(sequential), &sequential_funcs);
+    }
+    cbm_pipeline_free(sequential);
+
+    cbm_unsetenv("CBM_INDEX_SINGLE_THREAD");
+    cbm_setenv("CBM_WORKERS", "4", 1);
+    int parallel_rc[CX_ORDER_MT_RUNS];
+    char *parallel_sig[CX_ORDER_MT_RUNS];
+    for (int r = 0; r < CX_ORDER_MT_RUNS; r++) {
+        snprintf(db_path, sizeof(db_path), "%s/cx_parallel_%d.db", tmp, r);
+        cbm_pipeline_t *parallel = cbm_pipeline_new(tmp, db_path, CBM_MODE_FULL);
+        parallel_rc[r] = parallel ? cbm_pipeline_run(parallel) : -1;
+        parallel_sig[r] = NULL;
+        if (parallel && parallel_rc[r] == 0) {
+            int funcs = 0;
+            parallel_sig[r] =
+                cx_order_signature(db_path, cbm_pipeline_project_name(parallel), &funcs);
+        }
+        cbm_pipeline_free(parallel);
+    }
+
+    if (saved_workers) {
+        cbm_setenv("CBM_WORKERS", saved_workers, 1);
+        free(saved_workers);
+    } else {
+        cbm_unsetenv("CBM_WORKERS");
+    }
+    if (saved_single) {
+        cbm_setenv("CBM_INDEX_SINGLE_THREAD", saved_single, 1);
+        free(saved_single);
+    } else {
+        cbm_unsetenv("CBM_INDEX_SINGLE_THREAD");
+    }
+    th_rmtree(tmp);
+
+    /* Verdicts first, then release, then assert: the assertions must not leak. */
+    bool cycles_detected = sequential_sig && strstr(sequential_sig, "\"recursive\":true") != NULL;
+    int mismatch_run = -1;
+    char diff[CBM_SZ_1K] = "";
+    for (int r = 0; r < CX_ORDER_MT_RUNS && mismatch_run < 0; r++) {
+        if (parallel_rc[r] != 0 || !parallel_sig[r]) {
+            mismatch_run = r;
+            snprintf(diff, sizeof(diff), "run %d rc=%d", r, parallel_rc[r]);
+        } else if (sequential_sig &&
+                   cx_order_first_diff(sequential_sig, parallel_sig[r], diff, sizeof(diff))) {
+            mismatch_run = r;
+        }
+    }
+    free(sequential_sig);
+    for (int r = 0; r < CX_ORDER_MT_RUNS; r++) {
+        free(parallel_sig[r]);
+    }
+
+    ASSERT_EQ(sequential_rc, 0);
+    ASSERT_NOT_NULL(sequential_sig);
+    ASSERT_GTE(sequential_funcs, copied); /* at least the one function per fixture file */
+    ASSERT_TRUE(cycles_detected);        /* the cycles must reach the pass at all */
+    if (mismatch_run >= 0) {
+        printf("\n    parallel run %d diverges from sequential: %s\n", mismatch_run, diff);
+        FAIL("complexity props depend on worker id order");
+    }
+    PASS();
+}
+
 #ifdef _WIN32
 /* utimensat/AT_FDCWD do not exist on Windows. Set the same instant through
  * SetFileTime: FILETIME is 100ns ticks since 1601, the same representation
@@ -13455,6 +13675,7 @@ SUITE(pipeline) {
     RUN_TEST(pipeline_objectscript_export_aggregate_exceeds_arena_block_table);
     RUN_TEST(pipeline_env_access_configures_sequential_parallel_parity);
     RUN_TEST(pipeline_call_reference_sequential_parallel_edge_set_parity);
+    RUN_TEST(pipeline_complexity_props_independent_of_worker_order);
     RUN_TEST(pipeline_incremental_cross_file_call_reference_matches_fresh_full);
     RUN_TEST(pipeline_incremental_changed_target_invalidates_stale_inbound_call_reference);
     RUN_TEST(pipeline_incremental_parallel_registry_nodes_advance_shared_ids);