zig

commit 5672cd73bc50948cd1cdd2ee898b4e6333ebbfb1 (tree)
parent 52bfd87de71976773135e1204124c0180ed3a7c8
Author: Motiejus Jakštys <motiejus@jakstys.lt>
Date:   Fri, 13 Feb 2026 22:05:01 +0000

astgen: fix builtin_call ensure_result_used bit position

BuiltinCall.Flags has ensure_result_used at bit 1, not bit 3 like
Call/FieldCall. Separate the case to use the correct bit.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Diffstat:
M
astgen.c
 | 
16
+++++++++++-----

1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/astgen.c b/astgen.c
@@ -6560,17 +6560,23 @@ static bool addEnsureResult(
         uint32_t inst = maybe_unused_result - ZIR_REF_START_INDEX;
         ZirInstTag tag = ag->inst_tags[inst];
         switch (tag) {
-        // For call/field_call/builtin_call: set ensure_result_used flag
-        // (bit 3 of flags at offset 0). Flags *must* be at offset 0 in all
-        // three structs (AstGen.zig:2658-2665, Zir.zig:3022).
+        // For call/field_call: set ensure_result_used flag
+        // (bit 3 of flags at offset 0). Flags *must* be at offset 0
+        // (AstGen.zig:2658-2665, Zir.zig:3022).
         case ZIR_INST_CALL:
-        case ZIR_INST_FIELD_CALL:
-        case ZIR_INST_BUILTIN_CALL: {
+        case ZIR_INST_FIELD_CALL: {
             uint32_t pi = ag->inst_datas[inst].pl_node.payload_index;
             ag->extra[pi] |= (1u << 3); // ensure_result_used
             elide_check = true;
             break;
         }
+        // For builtin_call: ensure_result_used is at bit 1, not bit 3.
+        case ZIR_INST_BUILTIN_CALL: {
+            uint32_t pi = ag->inst_datas[inst].pl_node.payload_index;
+            ag->extra[pi] |= (1u << 1); // ensure_result_used
+            elide_check = true;
+            break;
+        }
         // Always noreturn → elide (AstGen.zig:2909).
         case ZIR_INST_BREAK:
         case ZIR_INST_BREAK_INLINE: