例子：

https://github.com/hc2088/libtest

post_install do |installer|
  installer.pods_project.targets.each do |target|
 
    puts target.name
    target.build_configurations.each do |config|
      puts config.name
      config.build_settings["IPHONEOS_DEPLOYMENT_TARGET"] = "12.0"
      config.build_settings['SWIFT_VERSION'] = '5.0'
      config.build_settings['ENABLE_BITCODE'] = 'NO'
      config.build_settings["EXCLUDED_ARCHS[sdk=iphonesimulator*]"] = "arm64"
      config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= [
        '$(inherited)',
        'AUDIO_SESSION_MICROPHONE=1',
      ]
    end
  end
end

执行pod install
输出：

 pod install
Analyzing dependencies
Downloading dependencies
Generating Pods project
Libtest
Release
Debug
Pods-test
Release
Debug
Integrating client project

installer.pods_project.targets.each do |target|这里的target只执行了2遍：
Libtest
Pods-test
并没有test壳工程自身？

对壳工程本身这里是test 这个target并没有生效：

image.png

对Pods targets 都有效：

image.png

#import <LibTest/Test.h>

@interface AppDelegate ()

@end

@implementation AppDelegate


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    [Test test];
    return YES;
}



@implementation Test
+(void)test{
    
#if AUDIO_SESSION_MICROPHONE
    NSLog(@"定义了AUDIO_SESSION_MICROPHONE");
#else
    NSLog(@"没有定义");
#endif
}
@end

EXCLUDED_ARCHS

同样也没有对壳工程的target起到作用：

image.png
image.png