diff --git a/llvm/Makefile.config.in b/llvm/Makefile.config.in
index d066e772cbb0..94dce300bbf3 100644
--- a/llvm/Makefile.config.in
+++ b/llvm/Makefile.config.in
@@ -265,3 +265,11 @@ BINDINGS_TO_BUILD := @BINDINGS_TO_BUILD@
 ALL_BINDINGS      := @ALL_BINDINGS@
 OCAML_LIBDIR      := @OCAML_LIBDIR@
 
+# When compiling under Mingw/Cygwin, executables such as tblgen
+# expect Windows paths, whereas the build system uses Unix paths.
+# The function SYSPATH transforms Unix paths into Windows paths.
+ifneq (,$(findstring -mno-cygwin, $(CXX)))
+  SYSPATH = $(shell echo $(1) | cygpath -m -f -)
+else
+  SYSPATH = $(1)
+endif
diff --git a/llvm/lib/VMCore/Makefile b/llvm/lib/VMCore/Makefile
index 2e283ec10cd7..35ef865b8f15 100644
--- a/llvm/lib/VMCore/Makefile
+++ b/llvm/lib/VMCore/Makefile
@@ -21,7 +21,7 @@ INTRINSICTDS := $(wildcard $(PROJ_SRC_ROOT)/include/llvm/Intrinsics*.td)
 
 $(ObjDir)/Intrinsics.gen.tmp: $(ObjDir)/.dir $(INTRINSICTDS) $(TBLGEN)
 	$(Echo) Building Intrinsics.gen.tmp from Intrinsics.td
-	$(Verb) $(TableGen) $(INTRINSICTD) -o $@ -gen-intrinsic
+	$(Verb) $(TableGen) $(call SYSPATH, $(INTRINSICTD)) -o $(call SYSPATH, $@) -gen-intrinsic
 
 $(GENFILE): $(ObjDir)/Intrinsics.gen.tmp
 	$(Verb) $(CMP) -s $@ $< || ( $(CP) $< $@ && \