Extended Description

Symptom: an Objective-C method declared as returning non-void, but without a return statement, produces no warning if the method contains an Obj-C exception handling block.

• (int)foo {
  // Missing return, -Wreturn-type is produced
  }

• (int)bar {
  @​try { }
  @​finally { }
  // Missing return but no warning!
  }

Root cause:
CFGBuilder simply does not have an implementation for ObjCAtTryStmt, ObjCAtCatchStmt, etc. It's been missing for 11 years.

There was briefly partial support:
89cc8ea

But it was removed:
89be652