Warning

This project is no longer maintained. See Apple's Build Settings Reference for a list of supported Xcode settings.

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Xcode Build Settings

A convenient reference of available build settings for Xcode projects.

For more information, see this NSHipster article.

Methodology

This website automatically generates its content from information found in Xcode configuration files. If you have Xcode installed locally, you can locate these files by running the following command in the Terminal:

$ find /Applications/Xcode.app/Contents/PlugIns/Xcode3Core.ideplugin \
    -iname "*.xcspec" -o \
    -iname "*.strings"
Plug-ins/Clang LLVM 1.0.xcplugin/Contents/Resources/Default Compiler.xcspec
# ...

Detailed Design

Xcode delegates much of its functionality across several plug-ins. Although few details about them are made available publicly, you could make a reasonable guess based on their name and content.

One of the more significant-looking Xcode plugins is one called Xcode3Core.ideplugin, which appears to handle details about the build system. If you look inside, you'll find that this plugin itself comprises several plugins, each named for a familiar technology.

If you peer still deeper into any of these — Metal.xcplugin, for example — you'll find .xcspec and .strings files.

An .xcspec file is a property list containing details about a compiler that's made available to the Xcode build system:

(
	{
		Type = Compiler;
		Identifier = "com.apple.compilers.metal";
		Name = "Metal Compiler";
		Description = "Compiles Metal files";
		CommandLine = "metal -c [options] [inputs]";
		RuleName = "CompileMetalFile [input]";
		ExecDescription = "Compile $(InputFile)";
		ProgressDescription = "Compiling $(CommandProgressByType) Metal files";
		InputFileTypes = (
			"sourcecode.metal",
		);
		Outputs = (
			"$(MTLCOMPILER_OUTPUT_FILE)",
		);
// ...

Also in this list are all the available build settings, including information about what kind of values can be passed and how they map to command-line arguments passed to the compiler:

{
    Name = "MTL_FAST_MATH";
    Type = Bool;
    DefaultValue = YES;
    Category = BuildOptions;
    CommandLineArgs = {
        YES = (
            "-ffast-math",
        );
        NO = (
            "-fno-fast-math",
        );
    };
}

Some .xcspec files have accompanying .strings files containing more human-readable descriptions of the build settings:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>Description</key>
	<string>Metal Compiler</string>
	<key>Name</key>
	<string>Metal Compiler</string>
	<key>Vendor</key>
	<string>Apple</string>
	<key>Version</key>
	<string>Default</string>
	<key>[BuildOptions]-category</key>
	<string>Build Options</string>
	<key>[MTL_COMPILER_FLAGS]-description</key>
    <string>Space-separated list of compiler flags</string>
    <!--- ... -->

This website combines these information sources to provide a single, coherant representation that can be readily searched and consulted.

Contact

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License

All code is published under the MIT License.

All content copyright © Apple Inc. All rights reserved.

NSHipster® and the NSHipster Logo are registered trademarks of Read Evaluate Press, LLC.

Core ML®, Metal®, OpenCL®, Siri®, Swift™, Xcode® and their respective logos are trademarks of Apple Inc.