Something changed, now 5800 compiler errors from precompiled header

Question

I apparently changed something in an iPhone Xcode project, and now when it precompiles the headers I'm getting

In file included from [...] /Foundation.framework/Headers/Foundation.h:8,
                 from [...] /UIKit.framework/Headers/UIAccelerometer.h:8,
                 from [...] /UIKit.framework/Headers/UIKit.h:9:
/Developer/Platforms/[...]/NSObjCRuntime.h:146: error: stray '@' in program
/Developer/Platforms/[...]/NSObjCRuntime.h:146: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'NSString'

and then 5800 more errors...

I'm hoping somebody else did this to themselves recently and can point me in the right direction!

Answer 1

GIYF:

http://forums.macrumors.com/archive/index.php/t-711554.html

Answer 2

As cdespinosa linked, you're compiling Objective-C as regular C++.

Go into the project settings and change the "Compile Sources As" to Objective-C++