Integrated Legacy v0.5.x decoder (provided by @inikep)
diff --git a/lib/Makefile b/lib/Makefile
index ce66ebb..5034891 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -52,7 +52,7 @@
 INCLUDEDIR=$(PREFIX)/include
 
 ZSTD_FILES := zstd_compress.c zstd_decompress.c fse.c huff0.c zdict.c divsufsort.c
-ZSTD_LEGACY:= legacy/zstd_v01.c legacy/zstd_v02.c legacy/zstd_v03.c legacy/zstd_v04.c
+ZSTD_LEGACY:= legacy/zstd_v01.c legacy/zstd_v02.c legacy/zstd_v03.c legacy/zstd_v04.c legacy/zstd_v05.c
 
 ifeq ($(ZSTD_LEGACY_SUPPORT), 0)
 CPPFLAGS  += -DZSTD_LEGACY_SUPPORT=0