From 01b454f8515312531ff0c70985203f9aecb022db Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Wed, 9 Mar 2022 17:12:40 +0200
Subject: [PATCH] AstGen: ensure lableld block implicitly ends in a break

---
 src/AstGen.zig          | 3 +++
 test/behavior/basic.zig | 7 +++++++
 2 files changed, 10 insertions(+)

diff --git a/src/AstGen.zig b/src/AstGen.zig
index bd8f06ae59..e39c7abffe 100644
--- a/src/AstGen.zig
+++ b/src/AstGen.zig
@@ -1991,6 +1991,9 @@ fn labeledBlockExpr(
     defer block_scope.labeled_breaks.deinit(astgen.gpa);
 
     try blockExprStmts(&block_scope, &block_scope.base, statements);
+    if (!block_scope.endsWithNoReturn()) {
+        _ = try block_scope.addBreak(.break_inline, block_inst, .void_value);
+    }
 
     if (!block_scope.label.?.used) {
         try astgen.appendErrorTok(label_token, "unused block label", .{});
diff --git a/test/behavior/basic.zig b/test/behavior/basic.zig
index 1ed7ea9faf..25a302398b 100644
--- a/test/behavior/basic.zig
+++ b/test/behavior/basic.zig
@@ -846,3 +846,10 @@ test "discarding the result of various expressions" {
     _ = while (S.bar()) |some| break some else {};
     _ = for ("foo") |char| break char else {};
 }
+
+test "labeled block implicitly ends in a break" {
+    var a = false;
+    blk: {
+        if (a) break :blk;
+    }
+}