diff options
| -rw-r--r-- | prog/types.go | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/prog/types.go b/prog/types.go index 45136f079..cbba259c9 100644 --- a/prog/types.go +++ b/prog/types.go @@ -704,10 +704,20 @@ func ForeachCallType(meta *Syscall, f func(t Type, ctx *TypeCtx)) { } func foreachTypeImpl(meta *Syscall, preorder bool, f func(t Type, ctx *TypeCtx)) { + // We need seen to be keyed by the type, the direction, and the optionality + // bit. Even if the first time we see a type it is optional or DirOut, it + // could be required or DirIn on another path. So to ensure that the + // information we report to the caller is correct, we need to visit both + // occurrences. + type seenKey struct { + t Type + d Dir + o bool + } // Note: we specifically don't create seen in ForeachType. // It would prune recursion more (across syscalls), but lots of users need to // visit each struct per-syscall (e.g. prio, used resources). - seen := make(map[Type]bool) + seen := make(map[seenKey]bool) var rec func(*Type, Dir, bool) rec = func(ptr *Type, dir Dir, optional bool) { if _, ref := (*ptr).(Ref); !ref { @@ -726,18 +736,28 @@ func foreachTypeImpl(meta *Syscall, preorder bool, f func(t Type, ctx *TypeCtx)) case *ArrayType: rec(&a.Elem, dir, optional) case *StructType: - if seen[a] { + key := seenKey{ + t: a, + d: dir, + o: optional, + } + if seen[key] { break // prune recursion via pointers to structs/unions } - seen[a] = true + seen[key] = true for i, f := range a.Fields { rec(&a.Fields[i].Type, f.Dir(dir), optional) } case *UnionType: - if seen[a] { + key := seenKey{ + t: a, + d: dir, + o: optional, + } + if seen[key] { break // prune recursion via pointers to structs/unions } - seen[a] = true + seen[key] = true for i, f := range a.Fields { rec(&a.Fields[i].Type, f.Dir(dir), optional) } |