Compile Error with: switch, “expected expression before”

In normal C you’d have to enclose this in brackets in both cases. I suspect this may fix your problem:

case 1:
{
    NSLog(@"");
    NSString *aStr;
    break;
}

See this SO question for more info.

Another way to get around this problem is to put a statement between the case label and the first declaration as you’ve done in your working example above. See the comments and Quinn Taylor’s answer for more info.