Compile failure with XCode 5.1

[Andrew M]

When compiling (running clang step) on Mac OSX with XCode 5.1, the flag "no-fused-madd" now causes error (full compile output below). Instead of just a warning, it flags it as an error, because of this change :

    Excerpt from XCode Release Notes::

        Apple LLVM compiler in Xcode 5.1 treats unrecognized command-line options as errors. This issue has been
        seen when building both Python native extensions and Ruby Gems, where some invalid compiler options are
        currently specified. Projects using invalid compiler options will need to be changed to remove those
        options. To help ease that transition, the compiler will temporarily accept an option to downgrade
        the error to a warning:

        -Wno-error=unused-command-line-argument-hard-error-in-future

Full XCode 5.1 release notes: https://developer.apple.com/library/mac/releasenotes/DeveloperTools/RN-Xcode/xc5_release_notes/xc5_release_notes.html

There is a workaround by setting environment variable prior to installing:

    >> export ARCHFLAGS='-Wno-error=unused-command-line-argument-hard-error-in-future'

But Apple is unclear as to when they will remove the downgrade error to warning, so eventually this workaround will go away as well.

Output of build configure :

running build_configure

checking for gcc... gcc

checking whether the C compiler works... yes

checking for C compiler default output file name... a.out

checking for suffix of executables...

checking whether we are cross compiling... no

checking for suffix of object files... o

checking whether we are using the GNU C compiler... yes

checking whether gcc accepts -g... yes

checking for gcc option to accept ISO C89... none needed

checking for __gmpz_init in -lgmp... no

checking for __gmpz_init in -lmpir... no

checking whether mpz_powm is declared... no

checking whether mpz_powm_sec is declared... no

checking how to run the C preprocessor... gcc -E

checking for grep that handles long lines and -e... /usr/bin/grep

checking for egrep... /usr/bin/grep -E

checking for ANSI C header files... yes

checking for sys/types.h... yes

checking for sys/stat.h... yes

checking for stdlib.h... yes

checking for string.h... yes

checking for memory.h... yes

checking for strings.h... yes

checking for inttypes.h... yes

checking for stdint.h... yes

checking for unistd.h... yes

checking for inttypes.h... (cached) yes

checking limits.h usability... yes

checking limits.h presence... yes

checking for limits.h... yes

checking stddef.h usability... yes

checking stddef.h presence... yes

checking for stddef.h... yes

checking for stdint.h... (cached) yes

checking for stdlib.h... (cached) yes

checking for string.h... (cached) yes

checking wchar.h usability... yes

checking wchar.h presence... yes

checking for wchar.h... yes

checking for inline... inline

checking for int16_t... yes

checking for int32_t... yes

checking for int64_t... yes

checking for int8_t... yes

checking for size_t... yes

checking for uint16_t... yes

checking for uint32_t... yes

checking for uint64_t... yes

checking for uint8_t... yes

checking for stdlib.h... (cached) yes

checking for GNU libc compatible malloc... yes

checking for memmove... yes

checking for memset... yes

configure: creating ./config.status

config.status: creating src/config.h

warning: GMP or MPIR library not found; Not building Crypto.PublicKey._fastmath.

building 'Crypto.Hash._MD2' extension

creating build/temp.macosx-10.9-intel-2.7

creating build/temp.macosx-10.9-intel-2.7/src

cc -fno-strict-aliasing -fno-common -dynamic -arch x86_64 -arch i386 -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -Wall -Wstrict-prototypes -Wshorten-64-to-32 -fwrapv -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch x86_64 -arch i386 -pipe -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/MD2.c -o build/temp.macosx-10.9-intel-2.7/src/MD2.o

clang: error: unknown argument: '-mno-fused-madd' [-Wunused-command-line-argument-hard-error-in-future]

clang: note: this will be a hard error (cannot be downgraded to a warning) in the future

error: command 'cc' failed with exit status 1