diff --git a/compiler/rustc_target/src/spec/mipsel_unknown_none.rs b/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
index 3288281cc03..1651ff9c2d6 100644
--- a/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
+++ b/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
@@ -1,4 +1,4 @@
-//! Bare MIPS32r2, little endian, softfloat
+//! Bare MIPS32r2, little endian, softfloat, O32 calling convention
 //!
 //! Can be used for MIPS M4K core (e.g. on PIC32MX devices)