diff --git a/rts/ghc.mk b/rts/ghc.mk
index 2182411962c5c2324b8e06bfe0c4ead6c0ef4bed..4f81e10dbd8f7a9358bf569cc253e65c9e59106f 100644
--- a/rts/ghc.mk
+++ b/rts/ghc.mk
@@ -277,6 +277,7 @@ sm/Storage_CC_OPTS += -Wno-strict-prototypes
 StgCRun_CC_OPTS += -w
 Typeable_CC_OPTS += -w
 RetainerProfile_CC_OPTS += -w
+RetainerSet_CC_OPTS += -Wno-format
 sm/Compact_CC_OPTS += -w
 # On Windows:
 win32/ConsoleHandler_CC_OPTS += -w