Update

vendor/github.com/go-json-experiment/json/internal/jsonopts/options.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !goexperiment.jsonv2 || !go1.25
+
 package jsonopts
 
 import (
@@ -63,7 +65,7 @@ func (*Struct) JSONOptions(internal.NotForPublicUse) {}
 
 // GetUnknownOption is injected by the "json" package to handle Options
 // declared in that package so that "jsonopts" can handle them.
-var GetUnknownOption = func(*Struct, Options) (any, bool) { panic("unknown option") }
+var GetUnknownOption = func(Struct, Options) (any, bool) { panic("unknown option") }
 
 func GetOption[T any](opts Options, setter func(T) Options) (T, bool) {
 	// Collapse the options to *Struct to simplify lookup.
@@ -102,14 +104,14 @@ func GetOption[T any](opts Options, setter func(T) Options) (T, bool) {
 		}
 		return any(structOpts.DepthLimit).(T), true
 	default:
-		v, ok := GetUnknownOption(structOpts, opt)
+		v, ok := GetUnknownOption(*structOpts, opt)
 		return v.(T), ok
 	}
 }
 
 // JoinUnknownOption is injected by the "json" package to handle Options
 // declared in that package so that "jsonopts" can handle them.
-var JoinUnknownOption = func(*Struct, Options) { panic("unknown option") }
+var JoinUnknownOption = func(Struct, Options) Struct { panic("unknown option") }
 
 func (dst *Struct) Join(srcs ...Options) {
 	dst.join(false, srcs...)
@@ -180,7 +182,7 @@ func (dst *Struct) join(excludeCoderOptions bool, srcs ...Options) {
 				}
 			}
 		default:
-			JoinUnknownOption(dst, src)
+			*dst = JoinUnknownOption(*dst, src)
 		}
 	}
 }