Commit da878dc0776b56c1e2c251857a40415a35e9535a | zig

author	Jacob Young <jacobly@ziglang.org> 2023-05-05 14:56:10-04:00
committer	Jacob Young <jacobly@ziglang.org> 2023-05-05 15:09:35-04:00
log	da878dc0776b56c1e2c251857a40415a35e9535a
tree	e575289a4a6145619f378987306d1913b7a94d84
parent	d70853ba39cb1694d91a763ea8492f3aed1494a7

AstGen: fix branch on undefined

`isAlwaysVoid` was being called with the undefined tag added by
`addOne`, causing non-deterministic behavior failures with release
builds of the compiler.  Prevents the following random failure:

    test/behavior/defer.zig:120:40: error: expected type 'error{One}', found 'void'

1 files changed, 4 insertions(+), 1 deletions(-)

src
- AstGen.zig

src/AstGen.zig+4-1

 @@ -2905,7 +2905,10 @@ fn deferStmt(
     const sub_scope = if (!have_err_code) &defer_gen.base else blk: {
         try gz.addDbgBlockBegin();
         const ident_name = try gz.astgen.identAsString(payload_token);
-        remapped_err_code = @intCast(u32, try gz.astgen.instructions.addOne(gz.astgen.gpa));
+        remapped_err_code = @intCast(Zir.Inst.Index, gz.astgen.instructions.len);
+        // Use a placeholder tag of .as to allow querying things that depend on the tag,
+        // but undefined data to prevent querying of data.bin.
+        try gz.astgen.instructions.append(gz.astgen.gpa, .{ .tag = .as, .data = undefined });
         const remapped_err_code_ref = Zir.indexToRef(remapped_err_code);
         local_val_scope = .{
             .parent = &defer_gen.base,