src/librustc_hir/weak_lang_items.rs

   1 //! Validity checking for weak lang items
   2
   3 use crate::def_id::DefId;
   4 use crate::{lang_items, LangItem, LanguageItems};
   5
   6 use rustc_data_structures::fx::FxHashMap;
   7 use rustc_span::symbol::{sym, Symbol};
   8 use syntax::ast;
   9
  10 use lazy_static::lazy_static;
  11
  12 macro_rules! weak_lang_items {
  13     ($($name:ident, $item:ident, $sym:ident;)*) => (
  14
  15 lazy_static! {
  16     pub static ref WEAK_ITEMS_REFS: FxHashMap<Symbol, LangItem> = {
  17         let mut map = FxHashMap::default();
  18         $(map.insert(sym::$name, lang_items::$item);)*
  19         map
  20     };
  21 }
  22
  23 pub fn link_name(attrs: &[ast::Attribute]) -> Option<Symbol> {
  24     lang_items::extract(attrs).and_then(|(name, _)| {
  25         $(if name == sym::$name {
  26             Some(sym::$sym)
  27         } else)* {
  28             None
  29         }
  30     })
  31 }
  32
  33 impl LanguageItems {
  34     pub fn is_weak_lang_item(&self, item_def_id: DefId) -> bool {
  35         let did = Some(item_def_id);
  36
  37         $(self.$name() == did)||*
  38     }
  39 }
  40
  41 ) }
  42
  43 weak_lang_items! {
  44     panic_impl,         PanicImplLangItem,          rust_begin_unwind;
  45     eh_personality,     EhPersonalityLangItem,      rust_eh_personality;
  46     eh_unwind_resume,   EhUnwindResumeLangItem,     rust_eh_unwind_resume;
  47     oom,                OomLangItem,                rust_oom;
  48 }