diff options
Diffstat (limited to 'pkg/compiler/check.go')
| -rw-r--r-- | pkg/compiler/check.go | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/pkg/compiler/check.go b/pkg/compiler/check.go index 8a1a7b7e9..d693fa790 100644 --- a/pkg/compiler/check.go +++ b/pkg/compiler/check.go @@ -949,7 +949,7 @@ func (comp *compiler) checkStructRecursion(checked map[string]bool, n *ast.Struc str += fmt.Sprintf("%v.%v -> ", elem.Struct, elem.Field) } str += name - comp.error(path[0].Pos, "recursive declaration: %v (mark some pointers as opt)", str) + comp.error(path[0].Pos, "recursive declaration: %v (mark some pointers as opt, or use variable-length arrays)", str) checked[name] = true return } @@ -975,6 +975,9 @@ func (comp *compiler) recurseField(checked map[string]bool, t *ast.Type, path [] if desc == typePtr && base.IsOptional { return // optional pointers prune recursion } + if desc == typeArray && len(args) == 1 { + return // variable-length arrays prune recursion + } for i, arg := range args { if desc.Args[i].Type == typeArgType { isArg := false @@ -1425,8 +1428,19 @@ func (comp *compiler) isVarlen(t *ast.Type) bool { } func (comp *compiler) isZeroSize(t *ast.Type) bool { + // We can recurse here for a struct that recursively contains itself in an array. + // In such case it's safe to say that it is zero size, because if all other fields are zero size, + // then the struct is indeed zero size (even if it contains several versions of itself transitively). + // If there are any other "normal" fields, then we will still correctly conclude that the whole struct + // is not zero size. + if comp.recursiveQuery[t] { + return true + } + comp.recursiveQuery[t] = true desc, args, _ := comp.getArgsBase(t, false) - return desc.ZeroSize != nil && desc.ZeroSize(comp, t, args) + res := desc.ZeroSize != nil && desc.ZeroSize(comp, t, args) + delete(comp.recursiveQuery, t) + return res } func (comp *compiler) checkVarlen(n *ast.Struct) { |