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xcode llvm 5 1 clang error using -'ios,xcode,compiler-construction,llvm'

xcode llvm 5 1 clang error  using -'ios,xcode,compiler-construction,llvm'

I am having no luck the last few days since Xcode 5.1 came out.

I keep getting this error on an old project that supports iOS 6.0:


clang: error: unknown argument: '-fno-obj-arc' [-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
Command /Applications/ failed with exit code 1

There are not many posts about this on the internet and some suggestions seem to be to change your CFLAGS but I have no idea how to do that in Xcode.

Apple suggests this from their documents:

  As of Apple LLVM compiler version 5.1 (clang-502) and later, the
  optimization level -O4 no longer implies link time optimization (LTO).
  In order to build with LTO explicitly use the -flto option in addition
  to the optimization level flag. (15633276) The 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
  Note: This option will not be supported in the future. To workaround
  this issue, set the ARCHFLAGS environment variable to downgrade the
  error to a warning. For example, you can install a Python native
  extension with:
  $ARCHFLAGS=-Wno-error=unused-command-line-argument-hard-error-in-future easy_install ExtensionName
  Similarly, you can install a Ruby Gem with:
  $ARCHFLAGS=-Wno-error=unused-command-line-argument-hard-error-in-future gem install GemName 16214764 updated

How do I get this workaround?  Obviously Apple has messed up because it should only be presenting me with a warning and not an error according to their documents.

Any help would be greatly appreciated.  I can not build my app until this issue is rectified.

asked Sep 7, 2015 by rajesh
0 votes

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