RustPython · youknowone · Sep 1, 2026 · Sep 1, 2026 · Sep 1, 2026
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -126,6 +126,14 @@ panic = "abort"
 
 [patch.crates-io]
 parking_lot_core = { git = "https://github.com/youknowone/parking_lot", branch = "rustpython" }
+# xz-core 0.1.0-rc.0 as published registers a `lzma12_optmap` static
+# initializer.  On MSVC it lands in `.CRT$XIB`, which `_initterm_e` walks as
+# `int (__cdecl *)(void)` while the initializer's Rust signature returns `()`,
+# so a Windows build exits 255 with empty stdout and stderr.  That release also
+# overflows the `alone_decoder` dictionary-size check in a debug build for
+# `dict_size == 0`.  simnalamburt/xz-rs#21 fixes both and is merged, so the pin
+# drops once a release carrying it reaches crates.io.
+xz-core = { git = "https://github.com/simnalamburt/xz-rs", rev = "5bf95411d0307e052ca2aeb06f0d75565c9a7362" }
 # REDOX START, Uncomment when you want to compile/check with redoxer
 # REDOX END
 
@@ -236,8 +244,7 @@ lexical-parse-float = "1.0.6"
 libc = "0.2.186"
 libffi = "5"
 libloading = "0.9"
-xz = "0.4.6-rc.0"
-xz-sys = "0.4.6-rc.0"
+xz-core = "0.1.0-rc.0"
 libsqlite3-sys = "0.38"
 libz-rs-sys = "0.6"
 zlib-rs = { version = "=0.6.7", default-features = false, features = ["rust-allocator", "__internal-api"] }

diff --git a/Lib/test/test_lzma.py b/Lib/test/test_lzma.py
@@ -143,7 +143,6 @@ def test_decompressor_chunks(self):
         self.assertTrue(lzd.eof)
         self.assertEqual(lzd.unused_data, b"")
 
-    @unittest.expectedFailure  # TODO: RUSTPYTHON; EOFError: End of stream already reached
     def test_decompressor_chunks_empty(self):
         lzd = LZMADecompressor()
         out = []
@@ -159,7 +158,6 @@ def test_decompressor_chunks_empty(self):
         self.assertTrue(lzd.eof)
         self.assertEqual(lzd.unused_data, b"")
 
-    @unittest.expectedFailure  # TODO: RUSTPYTHON; AttributeError: 'LZMADecompressor' object has no attribute 'check'
     def test_decompressor_chunks_maxsize(self):
         lzd = LZMADecompressor()
         max_length = 100
@@ -1352,7 +1350,6 @@ def test_tell_bad_args(self):
         f.close()
         self.assertRaises(ValueError, f.tell)
 
-    @unittest.expectedFailure  # TODO: RUSTPYTHON; AssertionError: True is not false
     def test_issue21872(self):
         # sometimes decompress data incompletely
 

diff --git a/crates/common/Cargo.toml b/crates/common/Cargo.toml
@@ -15,7 +15,7 @@ bz2 = ["std", "dep:bzip2"]
 cjk-codecs = []
 inet = ["std"]
 json = ["dep:memchr", "std"]
-lzma = ["std", "dep:xz", "dep:xz-sys"]
+lzma = ["std", "dep:xz-core"]
 std = []
 threading = ["parking_lot", "std"]
 wasm_js = ["getrandom/wasm_js"]
@@ -46,12 +46,7 @@ zlib-rs = { workspace = true, optional = true }
 lock_api = { workspace = true }
 siphasher = { workspace = true }
 num-complex = { workspace = true }
-
-[target.'cfg(not(any(target_os = "android", target_arch = "wasm32")))'.dependencies]
-# RustPython does not expose `_lzma` on these targets; keep the native engine's
-# dependency boundary with its common-module owner rather than in stdlib.
-xz = { workspace = true, optional = true }
-xz-sys = { workspace = true, optional = true }
+xz-core = { workspace = true, optional = true }
 
 [lints]
 workspace = true