下载Telegram for iOS源码
https://github.com/TelegramMessenger/Telegram-iOS

安装buck
https://buck.build/setup/getting_started.html

编译项目
https://github.com/TelegramMessenger/Telegram-iOS/issues/219#issuecomment-570533746

I have generated the Telegram_Buck.xcworkspace file, compiled successfully in Xcode 11.3, and run normally in the simulator.

Generate Telegram_Buck.xcworkspace method:

Need to install buck, and buck project can run normally.
Insert before include Utils.makefile in the Makefile file:

export BUCK=buck
export TELEGRAM_ENV_SET=1
export DEVELOPMENT_CODE_SIGN_IDENTITY=iPhone Distribution: Digital Fortress LLC (C67CF9S4VU)
export DISTRIBUTION_CODE_SIGN_IDENTITY=iPhone Distribution: Digital Fortress LLC (C67CF9S4VU)
export DEVELOPMENT_TEAM=C67CF9S4VU
export API_ID=8
export API_HASH=7245de8e747a0d6fbe11f7cc14fcc0bb
export BUNDLE_ID=ph.telegra.Telegraph
export IS_INTERNAL_BUILD=false
export IS_APPSTORE_BUILD=true
export APPSTORE_ID=686449807
export APP_SPECIFIC_URL_SCHEME=tgapp
export BUILD_NUMBER=199
export ENTITLEMENTS_APP=Telegram-iOS/Telegram-iOS-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_APP=match Development ph.telegra.Telegraph
export DISTRIBUTION_PROVISIONING_PROFILE_APP=match AppStore ph.telegra.Telegraph
export ENTITLEMENTS_EXTENSION_SHARE=Share/Share-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_EXTENSION_SHARE=match Development ph.telegra.Telegraph.Share
export DISTRIBUTION_PROVISIONING_PROFILE_EXTENSION_SHARE=match AppStore ph.telegra.Telegraph.Share
export ENTITLEMENTS_EXTENSION_WIDGET=Widget/Widget-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_EXTENSION_WIDGET=match Development ph.telegra.Telegraph.Widget
export DISTRIBUTION_PROVISIONING_PROFILE_EXTENSION_WIDGET=match AppStore ph.telegra.Telegraph.Widget
export ENTITLEMENTS_EXTENSION_NOTIFICATIONSERVICE=NotificationService/NotificationService-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_EXTENSION_NOTIFICATIONSERVICE=match Development ph.telegra.Telegraph.NotificationService
export DISTRIBUTION_PROVISIONING_PROFILE_EXTENSION_NOTIFICATIONSERVICE=match AppStore ph.telegra.Telegraph.NotificationService
export ENTITLEMENTS_EXTENSION_NOTIFICATIONCONTENT=NotificationContent/NotificationContent-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_EXTENSION_NOTIFICATIONCONTENT=match Development ph.telegra.Telegraph.NotificationContent
export DISTRIBUTION_PROVISIONING_PROFILE_EXTENSION_NOTIFICATIONCONTENT=match AppStore ph.telegra.Telegraph.NotificationContent
export ENTITLEMENTS_EXTENSION_INTENTS=SiriIntents/SiriIntents-AppStoreLLC.entitlements
export DEVELOPMENT_PROVISIONING_PROFILE_EXTENSION_INTENTS=match Development ph.telegra.Telegraph.SiriIntents
export DISTRIBUTION_PROVISIONING_PROFILE_EXTENSION_INTENTS=match AppStore ph.telegra.Telegraph.SiriIntents
export DEVELOPMENT_PROVISIONING_PROFILE_WATCH_APP=match Development ph.telegra.Telegraph.watchkitapp
export DISTRIBUTION_PROVISIONING_PROFILE_WATCH_APP=match AppStore ph.telegra.Telegraph.watchkitapp
export DEVELOPMENT_PROVISIONING_PROFILE_WATCH_EXTENSION=match Development ph.telegra.Telegraph.watchkitapp.watchkitextension
export DISTRIBUTION_PROVISIONING_PROFILE_WATCH_EXTENSION=match AppStore ph.telegra.Telegraph.watchkitapp.watchkitextension
export BUILDBOX_DIR=buildbox
export CODESIGNING_PROFILES_VARIANT=appstore
export PACKAGE_METHOD=appstore

Insert in SHARED_CONFIGS of Config/utils.bzl file:
    "DEAD_CODE_STRIPPING": "YES",

Execute the command make project