diff options
Diffstat (limited to 'src/librustc_codegen_llvm/attributes.rs')
| -rw-r--r-- | src/librustc_codegen_llvm/attributes.rs | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/src/librustc_codegen_llvm/attributes.rs b/src/librustc_codegen_llvm/attributes.rs index 8246bb24366..3b5f927d52f 100644 --- a/src/librustc_codegen_llvm/attributes.rs +++ b/src/librustc_codegen_llvm/attributes.rs @@ -226,13 +226,22 @@ pub fn provide(providers: &mut Providers) { pub fn provide_extern(providers: &mut Providers) { providers.wasm_import_module_map = |tcx, cnum| { + // Build up a map from DefId to a `NativeLibrary` structure, where + // `NativeLibrary` internally contains information about + // `#[link(wasm_import_module = "...")]` for example. + let native_libs = tcx.native_libraries(cnum); + let mut def_id_to_native_lib = FxHashMap(); + for lib in native_libs.iter() { + if let Some(id) = lib.foreign_module { + def_id_to_native_lib.insert(id, lib); + } + } + let mut ret = FxHashMap(); for lib in tcx.foreign_modules(cnum).iter() { - let attrs = tcx.get_attrs(lib.def_id); - let mut module = None; - for attr in attrs.iter().filter(|a| a.check_name("wasm_import_module")) { - module = attr.value_str(); - } + let module = def_id_to_native_lib + .get(&lib.def_id) + .and_then(|s| s.wasm_import_module); let module = match module { Some(s) => s, None => continue, @@ -244,7 +253,7 @@ pub fn provide_extern(providers: &mut Providers) { } Lrc::new(ret) - } + }; } fn wasm_import_module(tcx: TyCtxt, id: DefId) -> Option<CString> { |