Undefined Symbols with no other info

I'm getting 'undefined symbols' but it doesn't say what symbols!!

It took me a while to work this out....

1. Near the top left of the Xcode window there is a row of small grey icons. Click on the right-most one, which is a portrait rectangle with some broken horizontal lines in it.
2. In the new panel that appears below that row of icons, about the 5th row down has a grey hammer icon and the word "Build". Click on that.
3. Now look at the large top-right pane of the window. Scroll to the bottom and find the line that says "v (!) Link APPNAME".
4. At the far right end of that line, there is a small icon with about five grey horizontal lines. Click on that.
5. The pane will update. If necessary scroll down again.
6. Look for lines with a yellow (or red?) background. You should be able to spot the names of the undefined symbols.

Note that when you build again, the pane does not update; it continues to show the errors from the previous build. You need to click on all the buttons again.

Wow thank you! This is gold!

Interesting, now that I can see the detail it's referencing a function call instead of a library that its missing. More troubleshooting to do, thank you for the lead

ld: Undefined symbols: SplashScreen::createScene(), referenced from: AppDelegate::applicationDidFinishLaunching() in AppDelegate.o clang: error: linker command failed with exit code 1 (use -v to see invocation)

Oh GAWD the error was that it wasn't seeing any of my custom source files at all (and thus any functions that I had defined) because although I added them to the Xcode project I didn't add them to the build target (although build_all was checked by default). XCODE fail

Now it works thanks