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| author | Veikka Tuominen <git@vexu.eu> | 2020-12-26 02:36:12 +0200 |
|---|---|---|
| committer | Veikka Tuominen <git@vexu.eu> | 2020-12-26 02:36:12 +0200 |
| commit | a50759325c95ad7dfd1fbf029759cf0a2608b3ab (patch) | |
| tree | 8bdf7813a7b82e743ffc3dbc589314c94ba9473d /src | |
| parent | 40aad4f47e1ab02a1ff6109f4b6f06af00d1f503 (diff) | |
| download | zig-a50759325c95ad7dfd1fbf029759cf0a2608b3ab.tar.gz zig-a50759325c95ad7dfd1fbf029759cf0a2608b3ab.zip | |
stage2: add error for unused labels
Diffstat (limited to 'src')
| -rw-r--r-- | src/Module.zig | 2 | ||||
| -rw-r--r-- | src/astgen.zig | 23 |
2 files changed, 20 insertions, 5 deletions
diff --git a/src/Module.zig b/src/Module.zig index 3806c0dea8..c0b7011f43 100644 --- a/src/Module.zig +++ b/src/Module.zig @@ -804,7 +804,7 @@ pub const Scope = struct { pub const Label = struct { token: ast.TokenIndex, block_inst: *zir.Inst.Block, - result_loc: astgen.ResultLoc, + used: bool = false, }; }; diff --git a/src/astgen.zig b/src/astgen.zig index c4ac5b5fc9..7b6349d4a8 100644 --- a/src/astgen.zig +++ b/src/astgen.zig @@ -348,8 +348,9 @@ fn breakExpr(mod: *Module, parent_scope: *Scope, node: *ast.Node.ControlFlowExpr const block_inst = blk: { if (node.getLabel()) |break_label| { - if (gen_zir.label) |label| { + if (gen_zir.label) |*label| { if (try tokenIdentEql(mod, parent_scope, label.token, break_label)) { + label.used = true; break :blk label.block_inst; } } @@ -407,8 +408,9 @@ fn continueExpr(mod: *Module, parent_scope: *Scope, node: *ast.Node.ControlFlowE continue; }; if (node.getLabel()) |break_label| blk: { - if (gen_zir.label) |label| { + if (gen_zir.label) |*label| { if (try tokenIdentEql(mod, parent_scope, label.token, break_label)) { + label.used = true; break :blk; } } @@ -485,6 +487,9 @@ fn labeledBlockExpr( defer block_scope.instructions.deinit(mod.gpa); try blockExprStmts(mod, &block_scope.base, &block_node.base, block_node.statements()); + if (!block_scope.label.?.used) { + return mod.fail(parent_scope, tree.token_locs[block_node.label].start, "unused block label", .{}); + } block_inst.positionals.body.instructions = try block_scope.arena.dupe(*zir.Inst, block_scope.instructions.items); try gen_zir.instructions.append(mod.gpa, &block_inst.base); @@ -1398,7 +1403,7 @@ fn whileExpr(mod: *Module, scope: *Scope, rl: ResultLoc, while_node: *ast.Node.W loop_scope.break_block = while_block; loop_scope.continue_block = cond_block; if (while_node.label) |some| { - loop_scope.label = @as(?Scope.GenZIR.Label, Scope.GenZIR.Label{ + loop_scope.label = @as(?Scope.GenZIR.Label, Scope.GenZIR.Label{ .token = some, .block_inst = while_block, }); @@ -1465,6 +1470,11 @@ fn whileExpr(mod: *Module, scope: *Scope, rl: ResultLoc, while_node: *ast.Node.W condbr.positionals.else_body = .{ .instructions = try else_scope.arena.dupe(*zir.Inst, else_scope.instructions.items), }; + if (loop_scope.label) |some| { + if (!some.used) { + return mod.fail(scope, tree.token_locs[some.token].start, "unused while label", .{}); + } + } return &while_block.base; } @@ -1555,7 +1565,7 @@ fn forExpr(mod: *Module, scope: *Scope, rl: ResultLoc, for_node: *ast.Node.For) loop_scope.break_block = for_block; loop_scope.continue_block = cond_block; if (for_node.label) |some| { - loop_scope.label = @as(?Scope.GenZIR.Label, Scope.GenZIR.Label{ + loop_scope.label = @as(?Scope.GenZIR.Label, Scope.GenZIR.Label{ .token = some, .block_inst = for_block, }); @@ -1646,6 +1656,11 @@ fn forExpr(mod: *Module, scope: *Scope, rl: ResultLoc, for_node: *ast.Node.For) condbr.positionals.else_body = .{ .instructions = try else_scope.arena.dupe(*zir.Inst, else_scope.instructions.items), }; + if (loop_scope.label) |some| { + if (!some.used) { + return mod.fail(scope, tree.token_locs[some.token].start, "unused for label", .{}); + } + } return &for_block.base; } |