Apple just seeded another build of Xcode 4, Preview 6.  We’ve been hearing some good things about optimized speed which Apple alludes to in the release notes, embedded below:

New Features

Performance Measurement and Analysis

There is new command-line tool for measuring an application’s performance without launching the Instruments application: iprofiler. After making the measurements, you can analyze them with Instruments. A new framework, DTPerformanceSession (located in /Library/Developer/4.0/Instruments/Frameworks) allows your application to create performance measurements of itself or other applications. 7773305


General In the Manage Schemes dialog you can specify whether to create schemes automatically with the“Autocreate schemes” option. You may want to turn off automatic scheme creation in a large workspace, where automatic scheme creation produces too many schemes. This setting is shared with all the users of the workspace.

You can have Xcode create schemes with the Autocreate Schemes Now button. 7952053

You can add an Xcode archive file (.xcarchive) to the archives organizer by double-clicking it in the Finder. 8791305

You can use a workspace-relative location for derived data. 8242521

Task Information and Alerts Enhancements to the execution of alert scripts:

The scripts can access the Xcode user environment variables.

The value of the PWD environment variable is a path to the directory that contains the current project or workspace.

The new XcodeAlertAffectedPaths environment variable contains a colon-separated list of full paths to the affected files. This variable replaces the IDEAlertAffectedURLs environment variable. 8748528

Resolved Issues


Xcode doesn’t strip newline characters from the scripts in Run Script scheme actions. 8230045

Duplicating a scheme doesn’t result in a new scheme with broken target references. 8335950

When the active scheme is a unit-test scheme, clicking Run in the toolbar doesn’t produce an unknown error dialog. 8642393


Editing nib files: The Rename transformation renames action methods in Interface Builder documents when the action’s target is the first responder or the method is declared in a category, protocol, or a superclass of the given class. 8500272

Source Control and Snapshots: Xcode creates a snapshot of your workspace before performing a refactoring transformation. 7816256

Comparing Versions of a File

After you create a branch and switch to it in the repositories organizer, using the commit dialog or the version editor doesn’t cause an assertion failure. 8383245

Source Control and Snapshots

Xcode recognize SCP-based URLs (such as for Git repositories in the repositories organizer. 8044145


After you change General preferences > Build Location, Xcode uses the new build location. 7965261

New Issues

Performance Measurement and Analysis Multicore and Dispatch templates are not working. 8717719 Time Profiler and System Trace don’t work after installing Xcode 4.0 Developer Preview 6. Restart your computer. 8829655

If your computer contains more than one release of Xcode, the Dock time profiler doesn’t work correctly.

Add the Instruments application in the appropriate Xcode release to the Dock and restart your computer. 8830062

Known Issues


Interface Builder files with explicit Xcode 3 file types open in the source editor instead of in Interface Builder.

Set the file type of the Interface Builder file in the Identity and Type inspector to “Default,” deselect it in the project navigator, and select it again. 8028406

The task log viewer is empty when you select the last build task of a project or workspace in the log navigator and the viewer is set to show only recent operations.

Set the task log viewer to show all operations. 8350930

Editing Nib Files

Xcode cannot edit Mac OS X–type Interface Builder documents comprised of objects from frameworks other than AppKit.

You can compile and run these documents, however. 7470836 Refactoring: Xcode does not refactor Cocoa bindings. 8423815


Search navigator: Xcode may crash in the replace preview dialog of the search navigator when all the found instances are selected and you click Replace. 8091532

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