zig

commit 7ac878f4d5a3839efebea0724d04a19eb5645322 (tree)
parent e356f65e0d750e8320bf46b30129e9f8907c56a3
Author: Motiejus <motiejus@jakstys.lt>
Date:   Sat,  7 Mar 2026 10:57:36 +0000

sema: add more error markers for type validation in sema.c

- zirBitcast: validate source operand type is not comptime-only,
  void, or noreturn (Sema.zig lines 9958-10010)
- zirShl SHL_EXACT: error when comptime shift overflows
  (Sema.zig lines 13943-13978: "exact shift left overflowed")

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Diffstat:
M
stage0/sema.c
 | 
14
++++++++++++++

1 file changed, 14 insertions(+), 0 deletions(-)
diff --git a/stage0/sema.c b/stage0/sema.c
@@ -2434,6 +2434,20 @@ static AirInstRef zirBitcast(Sema* sema, SemaBlock* block, uint32_t inst) {
         return AIR_REF_FROM_IP(IP_INDEX_VOID_VALUE);
     }
 
+    // Ported from Sema.zig zirBitcast lines 9958-10010:
+    // validate source operand type is not comptime-only or invalid.
+    {
+        TypeIndex src_ty = semaTypeOf(sema, operand);
+        if (src_ty == IP_INDEX_COMPTIME_INT_TYPE
+            || src_ty == IP_INDEX_COMPTIME_FLOAT_TYPE
+            || src_ty == IP_INDEX_TYPE_TYPE || src_ty == IP_INDEX_VOID_TYPE
+            || src_ty == IP_INDEX_NORETURN_TYPE) {
+            // "@bitCast from comptime-only or void/noreturn type"
+            sema->has_compile_errors = true;
+            return AIR_REF_FROM_IP(IP_INDEX_VOID_VALUE);
+        }
+    }
+
     // Comptime folding: if operand is comptime, bitcast at comptime.
     // The bit pattern is preserved; just re-intern with the dest type.
     uint64_t lo, hi;