1 files changed, 54 insertions, 0 deletions
diff --git a/compiler/rustc_metadata/src/link_args.rs b/compiler/rustc_metadata/src/link_args.rs
new file mode 100644
index 00000000000..d8f16796083
--- /dev/null
+++ b/compiler/rustc_metadata/src/link_args.rs
@@ -0,0 +1,54 @@
+use rustc_hir as hir;
+use rustc_hir::itemlikevisit::ItemLikeVisitor;
+use rustc_middle::ty::TyCtxt;
+use rustc_span::symbol::{sym, Symbol};
+use rustc_target::spec::abi::Abi;
+
+crate fn collect(tcx: TyCtxt<'_>) -> Vec<String> {
+    let mut collector = Collector { tcx, args: Vec::new() };
+    tcx.hir().krate().visit_all_item_likes(&mut collector);
+
+    for attr in tcx.hir().krate().item.attrs.iter() {
+        if attr.has_name(sym::link_args) {
+            if let Some(linkarg) = attr.value_str() {
+                collector.add_link_args(linkarg);
+            }
+        }
+    }
+
+    collector.args
+}
+
+struct Collector<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    args: Vec<String>,
+}
+
+impl<'tcx> ItemLikeVisitor<'tcx> for Collector<'tcx> {
+    fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) {
+        let fm = match it.kind {
+            hir::ItemKind::ForeignMod(ref fm) => fm,
+            _ => return,
+        };
+        if fm.abi == Abi::Rust || fm.abi == Abi::RustIntrinsic || fm.abi == Abi::PlatformIntrinsic {
+            return;
+        }
+
+        // First, add all of the custom #[link_args] attributes
+        let sess = &self.tcx.sess;
+        for m in it.attrs.iter().filter(|a| sess.check_name(a, sym::link_args)) {
+            if let Some(linkarg) = m.value_str() {
+                self.add_link_args(linkarg);
+            }
+        }
+    }
+
+    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {}
+    fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem<'tcx>) {}
+}
+
+impl<'tcx> Collector<'tcx> {
+    fn add_link_args(&mut self, args: Symbol) {
+        self.args.extend(args.as_str().split(' ').filter(|s| !s.is_empty()).map(|s| s.to_string()))
+    }
+}