diff --git a/Makefile b/Makefile
index 241e638..8242000 100644
--- a/Makefile
+++ b/Makefile
@@ -19,7 +19,7 @@ CXX = g++
 # -O2, -O3 ... to find the best optimization level.
 # ===================================================================
 
-CXXFLAGS = -O3
+CXXFLAGS = -O3 -fPIC
 
 # PREDCXXFLAGS is for compiling J. Shewchuk's predicates.