diff --git a/src/libsyntax_ext/deriving/mod.rs b/src/libsyntax_ext/deriving/mod.rs
index 5582166c12e9c..fcbce36389082 100644
--- a/src/libsyntax_ext/deriving/mod.rs
+++ b/src/libsyntax_ext/deriving/mod.rs
@@ -338,10 +338,19 @@ fn hygienic_type_parameter(item: &Annotatable, base: &str) -> String {
/// Constructs an expression that calls an intrinsic
fn call_intrinsic(cx: &ExtCtxt,
- span: Span,
+ mut span: Span,
intrinsic: &str,
args: Vec
>)
-> P {
+ span.expn_id = cx.codemap().record_expansion(codemap::ExpnInfo {
+ call_site: span,
+ callee: codemap::NameAndSpan {
+ format: codemap::MacroAttribute(intern("derive")),
+ span: Some(span),
+ allow_internal_unstable: true,
+ },
+ });
+
let path = cx.std_path(&["intrinsics", intrinsic]);
let call = cx.expr_call_global(span, path, args);
diff --git a/src/test/run-pass-fulldeps/auxiliary/custom_derive_partial_eq.rs b/src/test/run-pass-fulldeps/auxiliary/custom_derive_partial_eq.rs
new file mode 100644
index 0000000000000..956f789dab839
--- /dev/null
+++ b/src/test/run-pass-fulldeps/auxiliary/custom_derive_partial_eq.rs
@@ -0,0 +1,81 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 or the MIT license
+// , at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// force-host
+
+#![feature(plugin_registrar, rustc_private, item_like_imports)]
+
+extern crate syntax;
+extern crate syntax_ext;
+extern crate rustc_plugin;
+
+use syntax_ext::deriving;
+use deriving::generic::*;
+use deriving::generic::ty::*;
+
+use rustc_plugin::Registry;
+use syntax::ast::*;
+use syntax::codemap::Span;
+use syntax::ext::base::*;
+use syntax::ext::build::AstBuilder;
+use syntax::parse::token::{intern, InternedString};
+use syntax::ptr::P;
+
+#[plugin_registrar]
+pub fn plugin_registrar(reg: &mut Registry) {
+ reg.register_syntax_extension(intern("derive_CustomPartialEq"),
+ MultiDecorator(Box::new(expand_deriving_partial_eq)));
+}
+
+fn expand_deriving_partial_eq(cx: &mut ExtCtxt, span: Span, mitem: &MetaItem, item: &Annotatable,
+ push: &mut FnMut(Annotatable)) {
+ // structures are equal if all fields are equal, and non equal, if
+ // any fields are not equal or if the enum variants are different
+ fn cs_eq(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> P {
+ cs_fold(true,
+ |cx, span, subexpr, self_f, other_fs| {
+ let other_f = (other_fs.len(), other_fs.get(0)).1.unwrap();
+ let eq = cx.expr_binary(span, BinOpKind::Eq, self_f, other_f.clone());
+ cx.expr_binary(span, BinOpKind::And, subexpr, eq)
+ },
+ cx.expr_bool(span, true),
+ Box::new(|cx, span, _, _| cx.expr_bool(span, false)),
+ cx,
+ span,
+ substr)
+ }
+
+ let inline = cx.meta_word(span, InternedString::new("inline"));
+ let attrs = vec!(cx.attribute(span, inline));
+ let methods = vec![MethodDef {
+ name: "eq",
+ generics: LifetimeBounds::empty(),
+ explicit_self: borrowed_explicit_self(),
+ args: vec!(borrowed_self()),
+ ret_ty: Literal(deriving::generic::ty::Path::new_local("bool")),
+ attributes: attrs,
+ is_unsafe: false,
+ unify_fieldless_variants: true,
+ combine_substructure: combine_substructure(Box::new(cs_eq)),
+ }];
+
+ let trait_def = TraitDef {
+ span: span,
+ attributes: Vec::new(),
+ path: deriving::generic::ty::Path::new(vec!["std", "cmp", "PartialEq"]),
+ additional_bounds: Vec::new(),
+ generics: LifetimeBounds::empty(),
+ is_unsafe: false,
+ supports_unions: false,
+ methods: methods,
+ associated_types: Vec::new(),
+ };
+ trait_def.expand(cx, mitem, item, push)
+}
diff --git a/src/test/run-pass-fulldeps/custom-derive-partial-eq.rs b/src/test/run-pass-fulldeps/custom-derive-partial-eq.rs
new file mode 100644
index 0000000000000..8cc7ab4219dc5
--- /dev/null
+++ b/src/test/run-pass-fulldeps/custom-derive-partial-eq.rs
@@ -0,0 +1,22 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 or the MIT license
+// , at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:custom_derive_partial_eq.rs
+// ignore-stage1
+// ignore-pretty : (#23623) problems when ending with // comments
+
+#![feature(plugin, custom_derive)]
+#![plugin(custom_derive_partial_eq)]
+#![allow(unused)]
+
+#[derive(CustomPartialEq)] // Check that this is not a stability error.
+enum E { V1, V2 }
+
+fn main() {}