Merge pull request #17504 from ziglang/fix-var-args-coercion

Sema: fix crash when coercion dest is var args

1 files changed, 21 insertions, 7 deletions

diff --git a/src/Sema.zig b/src/Sema.zig
index c9dacd1185..0f3ae46c1b 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -4371,13 +4371,19 @@ fn zirValidateRefTy(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileErr
     const mod = sema.mod;
     const un_tok = sema.code.instructions.items(.data)[inst].un_tok;
     const src = un_tok.src();
-    const ty_operand = sema.resolveType(block, src, un_tok.operand) catch |err| switch (err) {
-        error.GenericPoison => {
-            // We don't actually have a type, so this will be treated as an untyped address-of operator.
-            return;
-        },
+    // In case of GenericPoison, we don't actually have a type, so this will be
+    // treated as an untyped address-of operator.
+    if (un_tok.operand == .var_args_param_type) return;
+    const operand_air_inst = sema.resolveInst(un_tok.operand) catch |err| switch (err) {
+        error.GenericPoison => return,
+        else => |e| return e,
+    };
+    if (operand_air_inst == .var_args_param_type) return;
+    const ty_operand = sema.analyzeAsType(block, src, operand_air_inst) catch |err| switch (err) {
+        error.GenericPoison => return,
         else => |e| return e,
     };
+    if (ty_operand.isGenericPoison()) return;
     if (ty_operand.optEuBaseType(mod).zigTypeTag(mod) != .Pointer) {
         return sema.failWithOwnedErrorMsg(block, msg: {
             const msg = try sema.errMsg(block, src, "expected type '{}', found pointer", .{ty_operand.fmt(mod)});
@@ -9846,11 +9852,19 @@ fn analyzeAs(
     const mod = sema.mod;
     const operand = try sema.resolveInst(zir_operand);
     if (zir_dest_type == .var_args_param_type) return operand;
-    const dest_ty = sema.resolveType(block, src, zir_dest_type) catch |err| switch (err) {
+    const operand_air_inst = sema.resolveInst(zir_dest_type) catch |err| switch (err) {
+        error.GenericPoison => return operand,
+        else => |e| return e,
+    };
+    if (operand_air_inst == .var_args_param_type) return operand;
+    const dest_ty = sema.analyzeAsType(block, src, operand_air_inst) catch |err| switch (err) {
         error.GenericPoison => return operand,
         else => |e| return e,
     };
-    if (dest_ty.zigTypeTag(mod) == .NoReturn) {
+    const dest_ty_tag = dest_ty.zigTypeTagOrPoison(mod) catch |err| switch (err) {
+        error.GenericPoison => return operand,
+    };
+    if (dest_ty_tag == .NoReturn) {
         return sema.fail(block, src, "cannot cast to noreturn", .{});
     }
     const is_ret = if (Zir.refToIndex(zir_dest_type)) |ptr_index|