diff --git a/libretro-common/formats/png/Makefile b/libretro-common/formats/png/Makefile
index 4bbda953d9..46fde8a9f1 100644
--- a/libretro-common/formats/png/Makefile
+++ b/libretro-common/formats/png/Makefile
@@ -1,6 +1,6 @@
 TARGET := rpng
 
-SOURCES := rpng.c rpng_test.c
+SOURCES := rpng.c rpng_test.c ../../file/nbio/nbio_stdio.c
 OBJS := $(SOURCES:.c=.o)
 
 CFLAGS += -Wall -pedantic -std=gnu99 -O0 -g -DHAVE_ZLIB -DHAVE_ZLIB_DEFLATE -DRPNG_TEST -I../../include