Language: add labelled break and continue statements

[chqrlie]

• break and continue can take the label of an enclosing statement to break or continue directly, bypassing the nested code flow.
• simplified flow analysis
• add tests

[bvdberg]

Why would you use 'continue X' instead of 'goto X' (which is also what we generate)? When I read the title of the PR, I expected something like:

for(..) {
  while (..) {
     switch (..) {
       case 1:
        break while;
      case 2:
        break for;
      case 3:
        break;
     }
  }
}

So that we insert labels etc.

[chqrlie]

`continue X` expands to a goto but the label is not the same : the target label is inserted just before the } at the end of the block whereas the label X points to the `for` statement itself. Your suggestion to accept `for`, `while` and `switch` in `break` statements is interesting. it is less general and has no prior art but would be especially useful for a `switch` statement inside a `for` loop. Supporting that requires some extra work as we cannot use the existing label list.

…

On 1 Apr 2026, at 20:59, Bas van den Berg ***@***.***> wrote: bvdberg left a comment (c2lang/c2compiler#484) <#484?email_source=notifications&email_token=AE5F5KUPXLMATCVM764GTKD4TVRIZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMJXGIZTCMZSHE4KM4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2LK4DSL5RW63LNMVXHIX3POBSW4X3DNRUWG2Y#issuecomment-4172313298> Why would you use 'continue X' instead of 'goto X' (which is also what we generate)? When I read the title of the PR, I expected something like: for(..) { while (..) { switch (..) { case 1: break while; case 2: break for; case 3: break; } } } So that we insert labels etc. — Reply to this email directly, view it on GitHub <#484?email_source=notifications&email_token=AE5F5KUPXLMATCVM764GTKD4TVRIZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMJXGIZTCMZSHE4KM4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2LK4DSL5RW63LNMVXHIX3POBSW4X3DNRUWG2Y#issuecomment-4172313298>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AE5F5KSPDXRCXOZSA33MTZT4TVRIZAVCNFSM6AAAAACXIQFOCSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DCNZSGMYTGMRZHA>. You are receiving this because you authored the thread.

[chqrlie]

continue X expands to a goto but the label is not the same : the target label is inserted just before the } at the end of the block whereas the label X points to the for statement itself.
Your suggestion to accept for, while and switch in break statements is interesting. it is less general and has no prior art but would be especially useful for a switch statement inside a for loop. Supporting that requires some extra work as we cannot use the existing label list.