Expand global_asm! to nothing

crates/hir_expand/src/builtin_macro.rs

@@ -110,6 +110,7 @@ register_builtin! {
     (format_args_nl, FormatArgsNl) => format_args_expand,
     (llvm_asm, LlvmAsm) => asm_expand,
     (asm, Asm) => asm_expand,
+    (global_asm, GlobalAsm) => global_asm_expand,
     (cfg, Cfg) => cfg_expand,
     (core_panic, CorePanic) => panic_expand,
     (std_panic, StdPanic) => panic_expand,
@@ -274,6 +275,15 @@ fn asm_expand(
     ExpandResult::ok(expanded)
 }
 
+fn global_asm_expand(
+    _db: &dyn AstDatabase,
+    _id: LazyMacroId,
+    _tt: &tt::Subtree,
+) -> ExpandResult<tt::Subtree> {
+    // Expand to nothing (at item-level)
+    ExpandResult::ok(quote! {})
+}
+
 fn cfg_expand(
     db: &dyn AstDatabase,
     id: LazyMacroId,

crates/hir_expand/src/name.rs

@@ -221,6 +221,7 @@ pub mod known {
         option_env,
         llvm_asm,
         asm,
+        global_asm,
         // Builtin derives
         Copy,
         Clone,