Disable bitcode for project and cocoapods dependencies with Xcode 7?

To set this setting in a way that doesn't get overridden each time you do a pod install you can add this to your Podfile

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      config.build_settings['ENABLE_BITCODE'] = 'NO'
    end
  end
end

There is a way to build CocoaPods' targets with full bitcode. Just add -fembed-bitcode option to OTHER_CFLAGS of each:

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      cflags = config.build_settings['OTHER_CFLAGS'] || ['$(inherited)']
      cflags << '-fembed-bitcode'
      config.build_settings['OTHER_CFLAGS'] = cflags
    end
  end
end

I think this way is better than disabling bitcode.

project 'frameworkTest.xcodeproj'

# Uncomment this line to define a global platform for your project
platform :ios, '8.0'

target 'frameworkTest' do
  # Uncomment this line if you're using Swift or would like to use dynamic frameworks
  # use_frameworks!

  # Pods for frameworkTest
  source 'https://github.com/CocoaPods/Specs.git' 


#zip files libs
  pod 'SSZipArchive'

#reachability 
  pod 'Reachability'

end

#bitcode enable
post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|

      # set valid architecture
      config.build_settings['VALID_ARCHS'] = 'arm64 armv7 armv7s i386 x86_64'

      # build active architecture only (Debug build all)
      config.build_settings['ONLY_ACTIVE_ARCH'] = 'NO'

      config.build_settings['ENABLE_BITCODE'] = 'YES'

      if config.name == 'Release' || config.name == 'Pro'
          config.build_settings['BITCODE_GENERATION_MODE'] = 'bitcode'
      else # Debug
          config.build_settings['BITCODE_GENERATION_MODE'] = 'marker'
      end

      cflags = config.build_settings['OTHER_CFLAGS'] || ['$(inherited)']

      if config.name == 'Release' || config.name == 'Pro'
          cflags << '-fembed-bitcode'
      else # Debug
          cflags << '-fembed-bitcode-marker'
      end      

      config.build_settings['OTHER_CFLAGS'] = cflags
    end
  end
end

For disable bitcode for your own development pod only add this below code in pod file of the projects.

post_install do |installer|
    installer.pods_project.targets.each do |target|
        if target.name == "YOUR SDK TARGET NAME"
            puts "Processing for disable bit code in YOUR SDK TARGET NAME SDK"
            target.build_configurations.each do |config|
                config.build_settings['ENABLE_BITCODE'] = 'NO'
            end
        end
    end
end

In addition to @werediver's answer:

If you want to enable bitcode, In your post_install I suggest setting ['ENABLE_BITCODE'] = 'YES'. You can also add your deployment target (to stop XCode from complaining). In this case: ['IPHONEOS_DEPLOYMENT_TARGET'] = '12.0'

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      cflags = config.build_settings['OTHER_CFLAGS'] || ['$(inherited)']
      cflags << '-fembed-bitcode'
      config.build_settings['OTHER_CFLAGS'] = cflags
      config.build_settings['ENABLE_BITCODE'] = 'YES'
      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '12.0'
    end
  end
end

Disabling Bitcode in Main Project and Pods

The other answers fail to clear out the bitcode flag for the main project. The Post-Install hooks of the Cocoapod do not give you access to the main project, I believe this is design choice, so you need to find the project file and modify it using xcodeproj. If a binary library includes bitcode you will need to use xcrun bitcode_strip to remove the bitcode to make the project consistent.

Two helper functions

def disable_bitcode_for_target(target)
    target.build_configurations.each do |config|
      config.build_settings['ENABLE_BITCODE'] = 'NO'

      remove_cflags_matching(config.build_settings, ['-fembed-bitcode', '-fembed-bitcode-marker'])
    end
end

def remove_cflags_matching(build_settings, cflags)
  existing_cflags = build_settings['OTHER_CFLAGS']

  removed_cflags = []
  if !existing_cflags.nil?
    cflags.each do |cflag|
      existing_cflags.delete_if { |existing_cflag| existing_cflag == cflag && removed_cflags << cflag }
    end
  end

  if removed_cflags.length > 0
    build_settings['OTHER_CFLAGS'] = existing_cflags
  end
end

Post_install phase

post_install do |installer|    
  project_name = Dir.glob("*.xcodeproj").first
  project = Xcodeproj::Project.open(project_name)
  project.targets.each do |target|
    disable_bitcode_for_target(target)
  end
  project.save

  installer.pods_project.targets.each do |target|
    disable_bitcode_for_target(target)
  end

  installer.pods_project.save
end

Update for cocoapods 1.7+ if you have enabled multiple xcodeproj generation:

install! 'cocoapods', :generate_multiple_pod_projects => true

<Pod list section>

post_install do |installer|
    installer.pod_target_subprojects.each do |subproject|
        subproject.targets.each do |target|
            target.build_configurations.each do |config|
                config.build_settings['ENABLE_BITCODE'] = 'NO'
            end
        end
    end
end

If you have control over .podspec (i.e providing the pod using own specs / git repo)

s.pod_target_xcconfig = { 'ENABLE_BITCODE' => 'NO' }

Go to the build settings for the target you wish to disable it on. Search for something that says "Enable Bitcode", set it to No.