官方下載地址：https://www.openssl.org/source/

#解壓
$ tar -zxvf openssl-1.1.0h.tar.gz
$ cd openssl-1.1.0h

#配置（使用sudo是因為要prefix的訪問許可權）
$ sudo ./config --prefix=/usr/local/openssl
該步驟出現如下警告
Configured for darwin-i386-cc.
wanzhihuideMacBook-Pro:openssl-1.1.0h wanzhihui$ sudo ./config --prefix=/usr/local/ --openssldir=/usr/local/openssl darwin64-x86_64-cc
Operating system: i686-apple-darwinDarwin Kernel Version 15.0.0: Sat Sep 19 15:53:46 PDT 2015; root:xnu-3247.10.11~1/RELEASE_X86_64
WARNING! If you wish to build 64-bit library, then you have to
         invoke './Configure darwin64-x86_64-cc' *manually*.
         You have about 5 seconds to press Ctrl-C to abort.

openssl/config指令碼會根據$KERNEL_BITS來判斷是否開啟x86_64編譯，預設是不開啟的，所以你生成的openssl庫檔案是32位的，最後靜態連結到nginx會出錯。
解決方法：
找到makefile將裡面的PLATFORM=dist改成
PLATFORM=darwin64-x86_64-cc

#配置、編譯和安裝
$ export KERNEL_BITS=64
$ sudo ./config darwin64-x86_64-cc  --prefix=/usr/local/openssl
$ sudo make
$ sudo make install

#檢視版本
$ openssl version


不編譯64位的在安裝nginx時會報連結錯誤：
-L/usr/local/lib -lpcre /usr/local/openssl/lib/libssl.a /usr/local/openssl/lib/libcrypto.a -lz
ld: warning: ignoring file /usr/local/openssl/lib/libssl.a, file was built for archive which is not the architecture being linked (x86_64): /usr/local/openssl/lib/libssl.a
ld: warning: ignoring file /usr/local/openssl/lib/libcrypto.a, file was built for archive which is not the architecture being linked (x86_64): /usr/local/openssl/lib/libcrypto.a
Undefined symbols for architecture x86_64:
  "_ASN1_GENERALIZEDTIME_print", referenced from:
      _ngx_ssl_stapling_ocsp_handler in ngx_event_openssl_stapling.o
  "_ASN1_d2i_bio", referenced from:
      _ngx_ssl_stapling in ngx_event_openssl_stapling.o
  "_BIO_ctrl", referenced from:
      _ngx_ssl_get_raw_certificate in ngx_event_openssl.o
      _ngx_ssl_get_serial_number in ngx_event_openssl.o
      _ngx_ssl_stapling_ocsp_handler in ngx_event_openssl_stapling.o
  "_BIO_free", referenced from: