Error

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -c -pipe -DQT_NO_GRAPHICSVIEW -DQT_NO_GRAPHICSEFFECT -DQT_NO_STYLESHEET -DQT_NO_STYLE_CDE -DQT_NO_STYLE_CLEA
NLOOKS -DQT_NO_STYLE_MOTIF -DQT_NO_STYLE_PLASTIQUE -O2 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -mmacosx-version-min=10.6 -Wall -W -fP
IE  -I../../../mkspecs/macx-clang -I. -o openssl.o openssl.cpp                                                                                                                                            
openssl.cpp:42:10: fatal error: 'openssl/opensslv.h' file not found
#include <openssl/opensslv.h>
         ^
1 error generated.
Makefile:225: recipe for target 'openssl.o' failed
make: *** [openssl.o] Error 1
OpenSSL disabled.
OpenSSL support cannot be enabled due to functionality tests!
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rt.                                                                                                                                                                                                       
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builder for ‘/nix/store/ap3qdc3g9kryvlm3nyl2c0fpmvlkmaij-phantomjs-2.0.0-20150528.drv’ failed with exit code 1
error: build of ‘/nix/store/ap3qdc3g9kryvlm3nyl2c0fpmvlkmaij-phantomjs-2.0.0-20150528.drv’ failed