diff --git a/CMakeLists.txt b/CMakeLists.txt
index e108c16f8..17d7302ac 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,9 +5,6 @@ project(zlib C)
 
 set(VERSION "1.2.11.1")
 
-option(ASM686 "Enable building i686 assembly implementation")
-option(AMD64 "Enable building amd64 assembly implementation")
-
 set(INSTALL_BIN_DIR "${CMAKE_INSTALL_PREFIX}/bin" CACHE PATH "Installation directory for executables")
 set(INSTALL_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib" CACHE PATH "Installation directory for libraries")
 set(INSTALL_INC_DIR "${CMAKE_INSTALL_PREFIX}/include" CACHE PATH "Installation directory for headers")
@@ -129,39 +126,6 @@ if(NOT MINGW)
     )
 endif()
 
-if(CMAKE_COMPILER_IS_GNUCC)
-    if(ASM686)
-        set(ZLIB_ASMS contrib/asm686/match.S)
-    elseif (AMD64)
-        set(ZLIB_ASMS contrib/amd64/amd64-match.S)
-    endif ()
-
-	if(ZLIB_ASMS)
-		add_definitions(-DASMV)
-		set_source_files_properties(${ZLIB_ASMS} PROPERTIES LANGUAGE C COMPILE_FLAGS -DNO_UNDERLINE)
-	endif()
-endif()
-
-if(MSVC)
-    if(ASM686)
-		ENABLE_LANGUAGE(ASM_MASM)
-        set(ZLIB_ASMS
-			contrib/masmx86/inffas32.asm
-			contrib/masmx86/match686.asm
-		)
-    elseif (AMD64)
-		ENABLE_LANGUAGE(ASM_MASM)
-        set(ZLIB_ASMS
-			contrib/masmx64/gvmat64.asm
-			contrib/masmx64/inffasx64.asm
-		)
-    endif()
-
-	if(ZLIB_ASMS)
-		add_definitions(-DASMV -DASMINF)
-	endif()
-endif()
-
 # parse the full version number from zlib.h and include in ZLIB_FULL_VERSION
 file(READ ${CMAKE_CURRENT_SOURCE_DIR}/zlib.h _zlib_h_contents)
 string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
@@ -183,8 +147,8 @@ if(MINGW)
     set(ZLIB_DLL_SRCS ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj)
 endif(MINGW)
 
-add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_ASMS} ${ZLIB_DLL_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
-add_library(zlibstatic STATIC ${ZLIB_SRCS} ${ZLIB_ASMS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
+add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_DLL_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
+add_library(zlibstatic STATIC ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
 set_target_properties(zlib PROPERTIES DEFINE_SYMBOL ZLIB_DLL)
 set_target_properties(zlib PROPERTIES SOVERSION 1)