diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs
index 49365ace0e20c..4c25c85569b5d 100644
--- a/compiler/rustc_codegen_ssa/src/back/metadata.rs
+++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs
@@ -325,6 +325,7 @@ pub(crate) fn create_object_file(sess: &Session) -> Option<write::Object<'static
                 "" | "ilp32" | "lp64" => (),
                 "ilp32f" | "lp64f" => e_flags |= elf::EF_RISCV_FLOAT_ABI_SINGLE,
                 "ilp32d" | "lp64d" => e_flags |= elf::EF_RISCV_FLOAT_ABI_DOUBLE,
+                // Note that the `lp64e` is still unstable as it's not (yet) part of the ELF psABI.
                 "ilp32e" | "lp64e" => e_flags |= elf::EF_RISCV_RVE,
                 _ => bug!("unknown RISC-V ABI name"),
             }