Parser: allow labels at end of block in C23

Vexu · Nov 6, 2023 · 08bde2c · 08bde2c
1 parent 97c3de2
commit 08bde2c
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Showing 2 changed files with 17 additions and 3 deletions.
diff --git a/src/Diagnostics.zig b/src/Diagnostics.zig
@@ -2562,6 +2562,12 @@ const messages = struct {
         const kind = .@"error";
         const extra = .str;
     };
+    pub const label_compound_end = struct {
+        const msg = "label at end of compound statement is a C2x extension";
+        const opt = "c2x-extensions";
+        const kind = .warning;
+        const suppress_version = .c2x;
+    };
 };
 
 list: std.ArrayListUnmanaged(Message) = .{},

diff --git a/src/Parser.zig b/src/Parser.zig
@@ -4294,7 +4294,7 @@ fn labeledStmt(p: *Parser) Error!?NodeIndex {
 
         var labeled_stmt = Tree.Node{
             .tag = .labeled_stmt,
-            .data = .{ .decl = .{ .name = name_tok, .node = try p.stmt() } },
+            .data = .{ .decl = .{ .name = name_tok, .node = try p.labelableStmt() } },
         };
         labeled_stmt.ty = try Attribute.applyLabelAttributes(p, labeled_stmt.ty, attr_buf_top);
         return try p.addNode(labeled_stmt);
@@ -4341,7 +4341,7 @@ fn labeledStmt(p: *Parser) Error!?NodeIndex {
             try p.errStr(.case_not_in_switch, case, "case");
         }
 
-        const s = try p.stmt();
+        const s = try p.labelableStmt();
         if (second_item) |some| return try p.addNode(.{
             .tag = .case_range_stmt,
             .data = .{ .if3 = .{ .cond = s, .body = (try p.addList(&.{ first_item.node, some.node })).start } },
@@ -4351,7 +4351,7 @@ fn labeledStmt(p: *Parser) Error!?NodeIndex {
         });
     } else if (p.eatToken(.keyword_default)) |default| {
         _ = try p.expectToken(.colon);
-        const s = try p.stmt();
+        const s = try p.labelableStmt();
         const node = try p.addNode(.{
             .tag = .default_stmt,
             .data = .{ .un = s },
@@ -4370,6 +4370,14 @@ fn labeledStmt(p: *Parser) Error!?NodeIndex {
     } else return null;
 }
 
+fn labelableStmt(p: *Parser) Error!NodeIndex {
+    if (p.tok_ids[p.tok_i] == .r_brace) {
+        try p.err(.label_compound_end);
+        return p.addNode(.{ .tag = .null_stmt, .data = undefined });
+    }
+    return p.stmt();
+}
+
 const StmtExprState = struct {
     last_expr_tok: TokenIndex = 0,
     last_expr_res: Result = .{ .ty = .{ .specifier = .void } },