Validate maxvalue > 0 in SemLock and document winerror __reduce__ divergence

youknowone · youknowone · commit 457d123716a6 · 2026-02-23T21:03:38.000+09:00
diff --git a/crates/stdlib/src/multiprocessing.rs b/crates/stdlib/src/multiprocessing.rs
@@ -340,6 +340,9 @@ mod _multiprocessing {
             if args.kind != RECURSIVE_MUTEX && args.kind != SEMAPHORE {
                 return Err(vm.new_value_error("unrecognized kind".to_owned()));
             }
+            if args.maxvalue <= 0 {
+                return Err(vm.new_value_error("maxvalue must be positive".to_owned()));
+            }
             if args.value < 0 || args.value > args.maxvalue {
                 return Err(vm.new_value_error("invalid value".to_owned()));
             }
diff --git a/crates/vm/src/exceptions.rs b/crates/vm/src/exceptions.rs
@@ -2077,6 +2077,8 @@ pub(super) mod types {
                             args_reduced.push(vm.ctx.none());
                             args_reduced.push(filename2);
                         } else {
+                            // Diverges from CPython: include winerror even without
+                            // filename2 so it survives pickle round-trips.
                             #[cfg(windows)]
                             if let Some(winerror) = winerror {
                                 args_reduced.push(winerror);

Original file line number	Diff line number	Diff line change
`@@ -340,6 +340,9 @@ mod _multiprocessing {`
`340`	`340`	`if args.kind != RECURSIVE_MUTEX && args.kind != SEMAPHORE {`
`341`	`341`	`return Err(vm.new_value_error("unrecognized kind".to_owned()));`
`342`	`342`	`}`
	`343`	`+ if args.maxvalue <= 0 {`
	`344`	`+ return Err(vm.new_value_error("maxvalue must be positive".to_owned()));`
	`345`	`+ }`
`343`	`346`	`if args.value < 0 \|\| args.value > args.maxvalue {`
`344`	`347`	`return Err(vm.new_value_error("invalid value".to_owned()));`
`345`	`348`	`}`