diff --git a/compiler/cpp/Makefile.am b/compiler/cpp/Makefile.am
index f06b821..9063943 100644
--- a/compiler/cpp/Makefile.am
+++ b/compiler/cpp/Makefile.am
@@ -15,7 +15,6 @@
                  src/generate/t_xsd_generator.cc \
                  src/generate/t_perl_generator.cc \
                  src/generate/t_erl_generator.cc \
-                 src/generate/t_hs_generator.cc \
                  src/generate/t_cocoa_generator.cc \
                  src/generate/t_st_generator.cc \
                  src/generate/t_csharp_generator.cc \
@@ -62,6 +61,9 @@
 if THRIFT_GEN_ocaml
 thrift_SOURCES += src/generate/t_ocaml_generator.cc
 endif
+if THRIFT_GEN_hs
+thrift_SOURCES += src/generate/t_hs_generator.cc
+endif
 
 thrift_CXXFLAGS = -Wall -I$(srcdir)/src $(BOOST_CPPFLAGS)
 thrift_LDFLAGS = -Wall $(BOOST_LDFLAGS)