diff --git a/src/arch/x86_64/CodeGen.zig b/src/arch/x86_64/CodeGen.zig
index 23d99c72bd..c1d1c6863e 100644
--- a/src/arch/x86_64/CodeGen.zig
+++ b/src/arch/x86_64/CodeGen.zig
@@ -5268,7 +5268,7 @@ fn airArrayToSlice(self: *Self, inst: Air.Inst.Index) !void {
     const ptr_ty = self.air.typeOf(ty_op.operand);
     const ptr = try self.resolveInst(ty_op.operand);
     const array_ty = ptr_ty.childType();
-    const array_len = array_ty.arrayLenIncludingSentinel();
+    const array_len = array_ty.arrayLen();
     const result: MCValue = if (self.liveness.isUnused(inst)) .dead else blk: {
         const stack_offset = @intCast(i32, try self.allocMem(inst, 16, 16));
         try self.genSetStack(ptr_ty, stack_offset, ptr, .{});
diff --git a/test/behavior/cast.zig b/test/behavior/cast.zig
index c49e4bd44f..d6e8368e8e 100644
--- a/test/behavior/cast.zig
+++ b/test/behavior/cast.zig
@@ -497,7 +497,6 @@ test "single-item pointer of array to slice to unknown length pointer" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     try testCastPtrOfArrayToSliceAndPtr();
     comptime try testCastPtrOfArrayToSliceAndPtr();
@@ -821,7 +820,6 @@ test "peer cast [:x]T to []T" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const S = struct {
         fn doTheTest() !void {