port: advance VC6 typeobject frontier and preserve regression coverage

2026-10-26 18:09:33 +00:00
parent 35caf1a558
commit 5ab291a68c
162 changed files with 15675 additions and 85 deletions
@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+"""Guard _PyMem_DebugRawFree's C89 locals and NULL-safe evaluation order."""
+
+import re
+import sys
+from pathlib import Path
+
+source = Path(sys.argv[1]).read_text()
+match = re.search(
+    r"\n_PyMem_DebugRawFree\(void \*ctx, void \*p\)\s*\{(.*?)\n\}",
+    source, re.S,
+)
+assert match, "_PyMem_DebugRawFree definition not found"
+body = re.sub(r"/\*.*?\*/", "", match.group(1), flags=re.S)
+declarations = """
+    debug_alloc_api_t *api;
+    uint8_t *q;
+    size_t nbytes;
+"""
+assert body.split()[:len(declarations.split())] == declarations.split(), (
+    "_PyMem_DebugRawFree must declare api, q, and nbytes without initializers at function entry"
+)
+
+# Preserve the NULL return before either initializer is evaluated, especially
+# the pointer subtraction, and retain all subsequent operations in order.
+expected = declarations + """
+    if (p == NULL) {
+        return;
+    }
+    api = (debug_alloc_api_t *)ctx;
+    q = (uint8_t *)p - 2*SST;
+    _PyMem_DebugCheckAddress(__func__, api->api_id, p);
+    nbytes = read_size_t(q);
+    nbytes += PYMEM_DEBUG_EXTRA_BYTES;
+    memset(q, PYMEM_DEADBYTE, nbytes);
+    api->alloc.free(api->alloc.ctx, q);
+"""
+assert body.split() == expected.split(), (
+    "preserve _PyMem_DebugRawFree assignments after the NULL return and original operation order"
+)
+print("obmalloc _PyMem_DebugRawFree entry declarations and NULL-safe operation order: PASS")