可以先看官方文档：
生成 Xcode 项目
sh "源码路径/UnrealEngine/Engine/Build/BatchFiles/Mac/GenerateProjectFiles.sh" -project="工程路径/工程文件.uproject" -game -Engine
问题
Variable set but not used
开始编译 ShaderCompileWorker 时，可能会遇到下面的错误：
Showing All Errors Only
Variable 'MallocCrashOverhead' set but not used
Variable 'bDidStall' set but not used
Variable 'Result' set but not used
Variable 'MaxTaskThreads' set but not used
Variable 'TotalMemoryUsage' set but not used
Variable 'DeviceUtil' set but not used
Variable 'Memory' set but not used
Variable 'Cycles' set but not used
Variable 'HitRate' set but not used
Variable 'bDidSomething' set but not used
Variable 'bAnyImportArcsAdded' set but not used
Variable 'PkgCDO' set but not used
Variable 'PropagationFlags' set but not used
Variable 'bHandledWithCppStructOps' set but not used
Variable 'PreviousNonEditorOnly' set but not used
Variable 'Previous' set but not used
解决方案：
打开 UnrealEngine/Engine/Source/Programs/UnrealBuildTool/Platform/Mac/MacToolChain.cs文件：
if (CompileEnvironment.bEnableUndefinedIdentifierWarnings)
{
Result += " -Wundef" + (CompileEnvironment.bUndefinedIdentifierWarningsAsErrors ? "" : " -Wno-error=undef");
}
// https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
Result += " -Wno-deprecated";
Result += " -Wno-deprecated-declarations";
Result += " -Wno-int-to-void-pointer-cast";
Result += " -Wno-non-literal-null-conversion";
Result += " -Wno-overloaded-virtual";
Result += " -Wno-pointer-to-int-cast";
Result += " -Wno-pragma-once-outside-header";
Result += " -Wno-unused-but-set-variable";
Result += " -Wno-unused-function";
Result += " -Wno-unused-result";
Result += " -Wno-unused-variable";
Result += " -c";
参考：
