diff -Naur tcl8.6.5-orig/win/configure.in tcl8.6.5/win/configure.in
--- tcl8.6.5-orig/win/configure.in	2016-03-01 04:59:35.000000000 +0300
+++ tcl8.6.5/win/configure.in	2016-03-03 08:47:47.115572500 +0300
@@ -127,16 +127,7 @@
   tcl_ok=yes
 ])
 AS_IF([test "$tcl_ok" = "yes"], [
-  AC_SUBST(ZLIB_DLL_FILE,[\${ZLIB_DLL_FILE}])
-  AS_IF([test "$do64bit" != "no"], [
-    AS_IF([test "$GCC" == "yes"],[
-      AC_SUBST(ZLIB_LIBS,[\${ZLIB_DIR_NATIVE}/win64/libz.dll.a])
-    ], [
-      AC_SUBST(ZLIB_LIBS,[\${ZLIB_DIR_NATIVE}/win64/zdll.lib])
-    ])
-  ], [
-    AC_SUBST(ZLIB_LIBS,[\${ZLIB_DIR_NATIVE}/win32/zdll.lib])
-  ])
+  AC_SUBST(ZLIB_LIBS,[-lz])
 ], [
   AC_SUBST(ZLIB_OBJS,[\${ZLIB_OBJS}])
 ])
diff -Naur tcl8.6.5-orig/win/Makefile.in tcl8.6.5/win/Makefile.in
--- tcl8.6.5-orig/win/Makefile.in	2016-03-01 04:59:35.000000000 +0300
+++ tcl8.6.5/win/Makefile.in	2016-03-03 08:47:47.129571100 +0300
@@ -146,9 +146,8 @@
			  package ifneeded registry 1.3.4 [list load [file normalize ${REG_DLL_FILE}] registry]
 TEST_LOAD_FACILITIES	= package ifneeded Tcltest ${VERSION}@TCL_PATCH_LEVEL@ [list load [file normalize ${TEST_DLL_FILE}] Tcltest];\
			  $(TEST_LOAD_PRMS)
-ZLIB_DLL_FILE		= zlib1.dll
 
-SHARED_LIBRARIES 	= $(TCL_DLL_FILE) @ZLIB_DLL_FILE@
+SHARED_LIBRARIES 	= $(TCL_DLL_FILE)
 STATIC_LIBRARIES	= $(TCL_LIB_FILE)
 
 TCLSH			= tclsh$(VER)${EXESUFFIX}
@@ -188,7 +187,7 @@
 SHLIB_LD_LIBS	= @SHLIB_LD_LIBS@
 SHLIB_CFLAGS	= @SHLIB_CFLAGS@
 SHLIB_SUFFIX	= @SHLIB_SUFFIX@
-LIBS		= @LIBS@ $(shell $(CYGPATH) '@ZLIB_LIBS@')
+LIBS		= @LIBS@ @ZLIB_LIBS@
 
 RMDIR		= rm -rf
 MKDIR		= mkdir -p
@@ -466,14 +465,6 @@
 	@$(RM) ${TEST_DLL_FILE} ${TEST_LIB_FILE}
 	@MAKE_DLL@ ${TCLTEST_OBJS} $(TCL_STUB_LIB_FILE) $(SHLIB_LD_LIBS)
 
-# use pre-built zlib1.dll
-${ZLIB_DLL_FILE}: ${TCL_STUB_LIB_FILE}
-	@if test "@ZLIB_LIBS@set" != "${ZLIB_DIR_NATIVE}/win32/zdll.libset" ; then \
-		$(COPY) $(ZLIB_DIR)/win64/${ZLIB_DLL_FILE} ${ZLIB_DLL_FILE}; \
-	else \
-		$(COPY) $(ZLIB_DIR)/win32/${ZLIB_DLL_FILE} ${ZLIB_DLL_FILE}; \
-	fi;
-
 # Add the object extension to the implicit rules. By default .obj is not
 # automatically added.
 
@@ -579,7 +570,7 @@
 		else true; \
 		fi; \
 	    done;
-	@for i in $(TCL_DLL_FILE) $(ZLIB_DLL_FILE) $(TCLSH); \
+	@for i in $(TCL_DLL_FILE) $(TCLSH); \
 	    do \
 	    if [ -f $$i ]; then \
 		echo "Installing $$i to $(BIN_INSTALL_DIR)/"; \