Xcode 3.1 is a revision of the Xcode development environment. It is available both as a standalone version of Developer Tools for Mac OS X 10.5 (“Leopard”) as well as part of the iPhone SDK. Please see the Xcode 3.0 Release Notes for details about previous versions of Xcode.
Supported configurations
Xcode 3.1 will run on Mac OS X 10.5 (Leopard) on a Macintosh with either a PowerPC or an Intel processor. It will not install or run on earlier versions of Mac OS X. Xcode supports development for Mac OS X 10.3 (Panther) and Universal development for Mac OS X 10.4 (Tiger) and Mac OS X 10.5 (Leopard) using the Mac OS X SDK support. It also supports cross-development for the iPhone, iPod Touch, and iPhone Simulator using the iPhoneOS SDKs, but only on Macintosh computers with an Intel processor.
Xcode Installation
The default location for Xcode Developer Tools is /Developer. However, you may install Xcode 3.1 on any volume in any location, and you can move or rename the entire Developer directory after installation. The only restriction is that the directory names of its subdirectories must not be changed, nor moved within the developer directory; but the Developer directory itself may be renamed and placed in any other directory or volume, including servers and external drives.
This allows you to have multiple versions of Xcode tools installed on the same system but running independently. The Xcode IDE will use the SDKs, build tools, and auxiliary applications from the Developer directory it is launched from whenever possible, rather than those from the root system. To refer to those files in your own projects, use the new Relative to Xcode Folder reference style, whose root path is $(DEVELOPER_DIR).
The Xcode Developer Tools installer also installs the standard system development tools and interfaces into /usr, so conventional makefile- and config-based builds will operate correctly. Use the xcode-select tool to set the default tool set for command-line builds.
In all previous versions of Xcode and Project Builder, the first launch of Xcode for a new user would bring up a New User Assistant dialog to set the default Build directory location and some other preferences. This has been removed. If you are building projects that require a common build directory and are setting up a new user account, you must set this in the Xcode ▶ Preferences ▶ Building pane instead of the New User Assistant.
Project File Format Compatibility and Versioning
Xcode 3.1 reads and builds the targets of project files created in Xcode 2.1 through 3.0, and will automatically upgrade project files created in Xcode 1.5 through 2.0. Xcode 3.1 does not reliably read project files created in Xcode 1.2 or earlier, or Project Builder project files. Open and upgrade these project files in Xcode 2.5 before opening them with Xcode 3.1.
Note: It is strongly recommended that, when converting pre-Xcode 2.1 project files to Xcode 2.2 and later, you also upgrade all the project’s targets to Native Targets using the item in the Project menu. Many Xcode features, including support for building Universal Binaries, are not supported for non-native (“Jam-based”) targets.
Xcode 3.1 no longer imports CodeWarrior project files. Install Xcode 2.5 and CodeWarrior Pro version 8.3 and follow the documentation in Porting CodeWarrior Projects to Xcode.
Project files opened and edited with Xcode 3.1 are generally compatible with Xcode 3.0 and Xcode 2.5; this means that project files you create or open with Xcode 3.1 can always be opened and built with Xcode 3.0 and 2.5. If you use a particular feature that would cause your project to fail to build on a prior version of Xcode, you’ll see a Compatibility Notice in the lower right corner of your project window; see Project ▶ Get Info ▶ General ▶ Compatibility to investigate and resolve the compatibility issue.
New Default Factory Settings
Xcode 3.1 defines different default values for several Xcode Preferences. If you install Xcode on a machine where you have an existing user account, and you have explicitly set these preferences in the past, the new defaults will not affect you. If, however, you have always used Xcode’s default values for these preferences, or you create a new user account, you will see the effect of the different preferences. You may want to explicitly set the behavior you desire in Xcode ▶ Preferences.
General ▶ Automatically open/close attached editor is now checked by default
General ▶ Open Counterparts in Same Editor is now checked by default
CodeSense ▶ Show Arguments in Pop-up List is now unchecked by default
CodeSense ▶ Automatically Suggest is now set to Immediate
Building ▶ Continue building after errors is now checked by default
Indentation ▶ Syntax-Aware Indenting is now checked by default