diff --git a/src/librustc_codegen_llvm/consts.rs b/src/librustc_codegen_llvm/consts.rs
index 5a2d958038422..f0b5f4b887971 100644
--- a/src/librustc_codegen_llvm/consts.rs
+++ b/src/librustc_codegen_llvm/consts.rs
@@ -20,12 +20,14 @@ use monomorphize::MonoItem;
use common::{CodegenCx, val_ty};
use declare;
use monomorphize::Instance;
+use syntax_pos::Span;
+use syntax_pos::symbol::LocalInternedString;
use type_::Type;
use type_of::LayoutLlvmExt;
-use rustc::ty;
+use rustc::ty::{self, Ty};
use rustc::ty::layout::{Align, LayoutOf};
-use rustc::hir::{self, CodegenFnAttrFlags};
+use rustc::hir::{self, CodegenFnAttrs, CodegenFnAttrFlags};
use std::ffi::{CStr, CString};
@@ -119,6 +121,8 @@ pub fn get_static(cx: &CodegenCx, def_id: DefId) -> ValueRef {
let ty = instance.ty(cx.tcx);
let sym = cx.tcx.symbol_name(instance).as_str();
+ debug!("get_static: sym={} instance={:?}", sym, instance);
+
let g = if let Some(id) = cx.tcx.hir.as_local_node_id(def_id) {
let llty = cx.layout_of(ty).llvm_type(cx);
@@ -144,50 +148,15 @@ pub fn get_static(cx: &CodegenCx, def_id: DefId) -> ValueRef {
hir_map::NodeForeignItem(&hir::ForeignItem {
ref attrs, span, node: hir::ForeignItemKind::Static(..), ..
}) => {
- let g = if let Some(linkage) = cx.tcx.codegen_fn_attrs(def_id).linkage {
- // If this is a static with a linkage specified, then we need to handle
- // it a little specially. The typesystem prevents things like &T and
- // extern "C" fn() from being non-null, so we can't just declare a
- // static and call it a day. Some linkages (like weak) will make it such
- // that the static actually has a null value.
- let llty2 = match ty.sty {
- ty::TyRawPtr(ref mt) => cx.layout_of(mt.ty).llvm_type(cx),
- _ => {
- cx.sess().span_fatal(span, "must have type `*const T` or `*mut T`");
- }
- };
- unsafe {
- // Declare a symbol `foo` with the desired linkage.
- let g1 = declare::declare_global(cx, &sym, llty2);
- llvm::LLVMRustSetLinkage(g1, base::linkage_to_llvm(linkage));
-
- // Declare an internal global `extern_with_linkage_foo` which
- // is initialized with the address of `foo`. If `foo` is
- // discarded during linking (for example, if `foo` has weak
- // linkage and there are no definitions), then
- // `extern_with_linkage_foo` will instead be initialized to
- // zero.
- let mut real_name = "_rust_extern_with_linkage_".to_string();
- real_name.push_str(&sym);
- let g2 = declare::define_global(cx, &real_name, llty).unwrap_or_else(||{
- cx.sess().span_fatal(span,
- &format!("symbol `{}` is already defined", &sym))
- });
- llvm::LLVMRustSetLinkage(g2, llvm::Linkage::InternalLinkage);
- llvm::LLVMSetInitializer(g2, g1);
- g2
- }
- } else {
- // Generate an external declaration.
- declare::declare_global(cx, &sym, llty)
- };
-
- (g, attrs)
+ let fn_attrs = cx.tcx.codegen_fn_attrs(def_id);
+ (check_and_apply_linkage(cx, &fn_attrs, ty, sym, Some(span)), attrs)
}
item => bug!("get_static: expected static, found {:?}", item)
};
+ debug!("get_static: sym={} attrs={:?}", sym, attrs);
+
for attr in attrs {
if attr.check_name("thread_local") {
llvm::set_thread_local_mode(g, cx.tls_model);
@@ -197,19 +166,21 @@ pub fn get_static(cx: &CodegenCx, def_id: DefId) -> ValueRef {
g
} else {
// FIXME(nagisa): perhaps the map of externs could be offloaded to llvm somehow?
- // FIXME(nagisa): investigate whether it can be changed into define_global
- let g = declare::declare_global(cx, &sym, cx.layout_of(ty).llvm_type(cx));
+ debug!("get_static: sym={} item_attr={:?}", sym, cx.tcx.item_attrs(def_id));
+
+ let attrs = cx.tcx.codegen_fn_attrs(def_id);
+ let g = check_and_apply_linkage(cx, &attrs, ty, sym, None);
+
// Thread-local statics in some other crate need to *always* be linked
// against in a thread-local fashion, so we need to be sure to apply the
// thread-local attribute locally if it was present remotely. If we
// don't do this then linker errors can be generated where the linker
// complains that one object files has a thread local version of the
// symbol and another one doesn't.
- for attr in cx.tcx.get_attrs(def_id).iter() {
- if attr.check_name("thread_local") {
- llvm::set_thread_local_mode(g, cx.tls_model);
- }
+ if attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL) {
+ llvm::set_thread_local_mode(g, cx.tls_model);
}
+
if cx.use_dll_storage_attrs && !cx.tcx.is_foreign_item(def_id) {
// This item is external but not foreign, i.e. it originates from an external Rust
// crate. Since we don't know whether this crate will be linked dynamically or
@@ -242,6 +213,66 @@ pub fn get_static(cx: &CodegenCx, def_id: DefId) -> ValueRef {
g
}
+fn check_and_apply_linkage<'tcx>(
+ cx: &CodegenCx<'_, 'tcx>,
+ attrs: &CodegenFnAttrs,
+ ty: Ty<'tcx>,
+ sym: LocalInternedString,
+ span: Option<Span>
+) -> ValueRef {
+ let llty = cx.layout_of(ty).llvm_type(cx);
+ if let Some(linkage) = attrs.linkage {
+ debug!("get_static: sym={} linkage={:?}", sym, linkage);
+
+ // If this is a static with a linkage specified, then we need to handle
+ // it a little specially. The typesystem prevents things like &T and
+ // extern "C" fn() from being non-null, so we can't just declare a
+ // static and call it a day. Some linkages (like weak) will make it such
+ // that the static actually has a null value.
+ let llty2 = match ty.sty {
+ ty::TyRawPtr(ref mt) => cx.layout_of(mt.ty).llvm_type(cx),
+ _ => {
+ if span.is_some() {
+ cx.sess().span_fatal(span.unwrap(), "must have type `*const T` or `*mut T`")
+ } else {
+ bug!("must have type `*const T` or `*mut T`")
+ }
+ }
+ };
+ unsafe {
+ // Declare a symbol `foo` with the desired linkage.
+ let g1 = declare::declare_global(cx, &sym, llty2);
+ llvm::LLVMRustSetLinkage(g1, base::linkage_to_llvm(linkage));
+
+ // Declare an internal global `extern_with_linkage_foo` which
+ // is initialized with the address of `foo`. If `foo` is
+ // discarded during linking (for example, if `foo` has weak
+ // linkage and there are no definitions), then
+ // `extern_with_linkage_foo` will instead be initialized to
+ // zero.
+ let mut real_name = "_rust_extern_with_linkage_".to_string();
+ real_name.push_str(&sym);
+ let g2 = declare::define_global(cx, &real_name, llty).unwrap_or_else(||{
+ if span.is_some() {
+ cx.sess().span_fatal(
+ span.unwrap(),
+ &format!("symbol `{}` is already defined", &sym)
+ )
+ } else {
+ bug!("symbol `{}` is already defined", &sym)
+ }
+ });
+ llvm::LLVMRustSetLinkage(g2, llvm::Linkage::InternalLinkage);
+ llvm::LLVMSetInitializer(g2, g1);
+ g2
+ }
+ } else {
+ // Generate an external declaration.
+ // FIXME(nagisa): investigate whether it can be changed into define_global
+ declare::declare_global(cx, &sym, llty)
+ }
+}
+
pub fn codegen_static<'a, 'tcx>(
cx: &CodegenCx<'a, 'tcx>,
def_id: DefId,
diff --git a/src/test/run-pass/issue-18804/auxiliary/lib.rs b/src/test/run-pass/issue-18804/auxiliary/lib.rs
new file mode 100644
index 0000000000000..06d454b2c890a
--- /dev/null
+++ b/src/test/run-pass/issue-18804/auxiliary/lib.rs
@@ -0,0 +1,20 @@
+// Copyright 2018 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_type = "rlib"]
+#![feature(linkage)]
+
+pub fn foo<T>() -> *const() {
+ extern {
+ #[linkage = "extern_weak"]
+ static FOO: *const();
+ }
+ unsafe { FOO }
+}
diff --git a/src/test/run-pass/issue-18804/main.rs b/src/test/run-pass/issue-18804/main.rs
new file mode 100644
index 0000000000000..b5aa052034936
--- /dev/null
+++ b/src/test/run-pass/issue-18804/main.rs
@@ -0,0 +1,23 @@
+// Copyright 2018 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Test for issue #18804, #[linkage] does not propagate thorugh generic
+// functions. Failure results in a linker error.
+
+// ignore-asmjs no weak symbol support
+// ignore-emscripten no weak symbol support
+
+// aux-build:lib.rs
+
+extern crate lib;
+
+fn main() {
+ lib::foo::<i32>();
+}