--- ghc-7.4.1/ghc.mk	
+++ ghc-7.4.1/ghc.mk	
@@ -579,7 +579,6 @@ BUILD_DIRS += \
    driver/ghci \
    driver/ghc \
    driver/haddock \
-   libffi \
    includes \
    rts
 
--- ghc-7.4.1/rts/ghc.mk	
+++ ghc-7.4.1/rts/ghc.mk	
@@ -86,8 +86,7 @@ 
 ALL_RTS_DEF_LIBNAMES 	= base ghc-prim
 ALL_RTS_DEF_LIBS	= \
 	rts/dist/build/win32/libHSbase.dll.a \
-	rts/dist/build/win32/libHSghc-prim.dll.a \
-	libffi/build/inst/lib/libffi.dll.a
+	rts/dist/build/win32/libHSghc-prim.dll.a 
 
 # -- import libs for the regular Haskell libraries
 define make-importlib-def # args $1 = lib name
@@ -172,12 +171,12 @@ 
 # Making a shared library for the RTS.
 ifneq "$$(findstring dyn, $1)" ""
 ifeq "$$(HOSTPLATFORM)" "i386-unknown-mingw32"
-$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(ALL_RTS_DEF_LIBS) rts/libs.depend rts/dist/build/libffi-5.dll
+$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(ALL_RTS_DEF_LIBS) rts/libs.depend
 	"$$(RM)" $$(RM_OPTS) $$@
 	"$$(rts_dist_HC)" -package-name rts -shared -dynamic -dynload deploy \
 	  -no-auto-link-packages -Lrts/dist/build -lffi-5 `cat rts/libs.depend` $$(rts_$1_OBJS) $$(ALL_RTS_DEF_LIBS) -o $$@
 else
-$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS) rts/libs.depend rts/dist/build/libffi$$(soext)
+$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS) rts/libs.depend
 	"$$(RM)" $$(RM_OPTS) $$@
 	"$$(rts_dist_HC)" -package-name rts -shared -dynamic -dynload deploy \
 	  -no-auto-link-packages -Lrts/dist/build -lffi `cat rts/libs.depend` $$(rts_$1_OBJS) \
@@ -188,9 +187,9 @@ 
 endif
 endif
 else
-$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS) $$(rts_ffi_objs_stamp)
+$$(rts_$1_LIB) : $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS)
 	"$$(RM)" $$(RM_OPTS) $$@
-	echo $$(rts_ffi_objs) $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS) | "$$(XARGS)" $$(XARGS_OPTS) "$$(AR_STAGE1)" \
+	echo $$(rts_$1_OBJS) $$(rts_$1_DTRACE_OBJS) | "$$(XARGS)" $$(XARGS_OPTS) "$$(AR_STAGE1)" \
 		$$(AR_OPTS_STAGE1) $$(EXTRA_AR_ARGS_STAGE1) $$@
 endif
 
@@ -403,6 +402,12 @@ 
 rts/dist/build/sm/Evac_thr_CC_OPTS += -DPARALLEL_GC -Irts/sm
 rts/dist/build/sm/Scav_thr_CC_OPTS += -DPARALLEL_GC -Irts/sm
 
+# Use system libffi
+libffi_include_flags:=$(shell pkg-config --cflags-only-I libffi)
+rts/Adjustor_CC_OPTS += $(libffi_include_flags)
+rts/Interpreter_CC_OPTS += $(libffi_include_flags)
+rts/sm/Storage_CC_OPTS += $(libffi_include_flags)
+
 #-----------------------------------------------------------------------------
 # Add PAPI library if needed
 
@@ -504,10 +509,8 @@ 
 # installing
 
 INSTALL_LIBS += $(ALL_RTS_LIBS)
-INSTALL_LIBS += $(wildcard rts/dist/build/libffi$(soext)*)
-INSTALL_LIBS += $(wildcard rts/dist/build/libffi-5.dll)
 
-install: install_libffi_headers
+install:
 
 .PHONY: install_libffi_headers
 install_libffi_headers :
--- ghc-7.4.1/rts/package.conf.in	
+++ ghc-7.4.1/rts/package.conf.in	
@@ -24,8 +24,9 @@ 
 hs-libraries:   "HSrts"
 
 extra-libraries:
+				"ffi"
 #ifdef HAVE_LIBM
-                		"m"		/* for ldexp() */
+			      , "m"		/* for ldexp() */
 #endif
 #ifdef HAVE_LIBRT
 			      , "rt"
--- ghc-7.4.1/compiler/ghc.mk	
+++ ghc-7.4.1/compiler/ghc.mk	
@@ -260,6 +260,8 @@ 
 
 compiler_CPP_OPTS += -I$(GHC_INCLUDE_DIR)
 compiler_CPP_OPTS += ${GhcCppOpts}
+libffi_include_flags := $(shell pkg-config --cflags-only-I libffi)
+compiler/ghci/LibFFI_HSC2HS_OPTS += $(addprefix --cflag=,$(libffi_include_flags))
 
 $(PRIMOPS_TXT) compiler/parser/Parser.y: %: %.pp compiler/stage1/$(PLATFORM_H)
 	$(CPP) $(RAWCPP_FLAGS) -P $(compiler_CPP_OPTS) -x c $< | grep -v '^#pragma GCC' > $@