fix ICE in pretty-printing global_asm! const operands

Author: folkertdev

compiler/rustc_middle/src/mir/pretty.rs

@@ -653,7 +653,7 @@ fn write_mir_sig(tcx: TyCtxt<'_>, body: &Body<'_>, w: &mut dyn io::Write) -> io:
             write!(w, "static mut ")?
         }
         (_, _) if is_function => write!(w, "fn ")?,
-        (DefKind::AnonConst | DefKind::InlineConst, _) => {} // things like anon const, not an item
+        (DefKind::AnonConst | DefKind::InlineConst | DefKind::GlobalAsm, _) => {} // things like anon const, not an item
         _ => bug!("Unexpected def kind {:?}", kind),
     }
 

tests/ui/unpretty/mir/global-asm-const.rs

@@ -0,0 +1,13 @@
+//@ compile-flags: -Zdump-mir=all --crate-type=lib
+//@ needs-asm-support
+//@ check-pass
+
+use std::arch::{asm, global_asm};
+
+// test that pretty mir printing of `const` operands in `global_asm!` does not ICE
+
+global_asm!("/* {} */", const 5);
+
+pub fn foo() {
+    unsafe { asm!("/* {} */", const 5) };
+}