From 1973ee479d83f06aea2366963d5ec092d8c591dc Mon Sep 17 00:00:00 2001 From: Steven Fackler Date: Sun, 17 May 2015 14:03:37 -0700 Subject: Make #[derive(Debug)] work with unsized fields Closes #25394 --- src/libsyntax/ext/deriving/show.rs | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'src/libsyntax') diff --git a/src/libsyntax/ext/deriving/show.rs b/src/libsyntax/ext/deriving/show.rs index 518bd161c1e..9dcbd2d1f70 100644 --- a/src/libsyntax/ext/deriving/show.rs +++ b/src/libsyntax/ext/deriving/show.rs @@ -75,6 +75,7 @@ fn show_substructure(cx: &mut ExtCtxt, span: Span, match *substr.fields { Struct(ref fields) | EnumMatching(_, _, ref fields) => { + if fields.is_empty() || fields[0].name.is_none() { // tuple struct/"normal" variant expr = cx.expr_method_call(span, @@ -83,11 +84,14 @@ fn show_substructure(cx: &mut ExtCtxt, span: Span, vec![name]); for field in fields { + // Use double indirection to make sure this works for unsized types + let field = cx.expr_addr_of(field.span, field.self_.clone()); + let field = cx.expr_addr_of(field.span, field); + expr = cx.expr_method_call(span, expr, token::str_to_ident("field"), - vec![cx.expr_addr_of(field.span, - field.self_.clone())]); + vec![field]); } } else { // normal struct/struct variant @@ -100,12 +104,14 @@ fn show_substructure(cx: &mut ExtCtxt, span: Span, let name = cx.expr_lit(field.span, ast::Lit_::LitStr( token::get_ident(field.name.clone().unwrap()), ast::StrStyle::CookedStr)); + + // Use double indirection to make sure this works for unsized types + let field = cx.expr_addr_of(field.span, field.self_.clone()); + let field = cx.expr_addr_of(field.span, field); expr = cx.expr_method_call(span, expr, token::str_to_ident("field"), - vec![name, - cx.expr_addr_of(field.span, - field.self_.clone())]); + vec![name, field]); } } } -- cgit 1.4.1-3-g733a5