diff --git a/programs/Makefile b/programs/Makefile
index db718d14c..407a4f374 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -24,7 +24,9 @@ else
 ALIGN_LOOP =
 endif
 
-CPPFLAGS+= -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(ZSTDDIR)/compress -I$(ZSTDDIR)/dictBuilder
+CPPFLAGS+= -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(ZSTDDIR)/compress \
+           -I$(ZSTDDIR)/dictBuilder \
+           -DXXH_NAMESPACE=ZSTD_   # because xxhash.o already compiled with this macro from library
 CFLAGS  ?= -O3
 DEBUGFLAGS = -g -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
           -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \