diff --git a/arch/m32r/boot/compressed/Makefile b/arch/m32r/boot/compressed/Makefile
index 177716b1d613..01729c2979ba 100644
--- a/arch/m32r/boot/compressed/Makefile
+++ b/arch/m32r/boot/compressed/Makefile
@@ -43,9 +43,9 @@ endif
 
 OBJCOPYFLAGS += -R .empty_zero_page
 
-suffix_$(CONFIG_KERNEL_GZIP)	= gz
-suffix_$(CONFIG_KERNEL_BZIP2)	= bz2
-suffix_$(CONFIG_KERNEL_LZMA)	= lzma
+suffix-$(CONFIG_KERNEL_GZIP)	= gz
+suffix-$(CONFIG_KERNEL_BZIP2)	= bz2
+suffix-$(CONFIG_KERNEL_LZMA)	= lzma
 
 $(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/vmlinux.bin.$(suffix-y) FORCE
 	$(call if_changed,ld)