I did get compiling from source to work on the Mac. Unfortunately I'm not sure what the problem was.
I now see a new problem, not sure if it is a ghc problem or a library problem:
cabal install HsOpenSSL
...
Building HsOpenSSL-0.11.1.1...
Preprocessing library HsOpenSSL-0.11.1.1...
In file included from BN.hsc:45:
cbits/HsOpenSSL.h:3:10: fatal error: 'openssl/asn1.h' file not found
#include <openssl/asn1.h>
^
1 error generated.
compiling dist/build/OpenSSL/BN_hsc_make.c failed (exit code 1)
command was: /usr/bin/gcc -c dist/build/OpenSSL/BN_hsc_make.c -o dist/build/OpenSSL/BN_hsc_make.o -m64 -fno-stack-protector -D__GLASGOW_HASKELL__=710 -Ddarwin_BUILD_OS=1 -Dx86_64_BUILD_ARCH=1 -Ddarwin_HOST_OS=1 -Dx86_64_HOST_ARCH=1 -Icbits -D PTHREAD -DCALLCONV=ccall -Idist/build/autogen -include dist/build/autogen/cabal_macros.h -I/Users/gcolpitts/Library/Haskell/ghc-7.10.2.20151105-x86_64/lib/network-2.6.2.1/include -I/usr/local/lib/ghc-7.10.2.20151105/unix_KZL8h98IqDM57kQSPo1mKx/include -I/usr/local/lib/ghc-7.10.2.20151105/time_FTheb6LSxyX1UABIbBXRfn/include -I/usr/local/lib/ghc-7.10.2.20151105/bytes_6VWy06pWzJq9evDvK2d4w6/include -I/usr/local/lib/ghc-7.10.2.20151105/base_HQfYBxpPvuw8OunzQu6JGM/include -I/usr/local/lib/ghc-7.10.2.20151105/integ_2aU3IZNMF9a7mQ0OzsZ0dS/include -I/usr/local/lib/ghc-7.10.2.20151105/include -I/usr/local/lib/ghc-7.10.2.20151105/include/
cabal: Error: some packages failed to install:
HsOpenSSL-0.11.1.1 failed during the building phase. The exception was:
ExitFailure 1
/usr/bin/gcc --version
/usr/bin/gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/usr/include/c++/4.2.1
Apple LLVM version 7.0.0 (clang-700.1.76)
Target: x86_64-apple-darwin15.0.0
Thread model: posix