diff --git a/src/arch/x86_64/CodeGen.zig b/src/arch/x86_64/CodeGen.zig
index 6a6022b62d..90c777aa45 100644
--- a/src/arch/x86_64/CodeGen.zig
+++ b/src/arch/x86_64/CodeGen.zig
@@ -803,6 +803,7 @@ const InstTracking = struct {
                 remaining_reg = tracked_reg;
             };
             assert(found_reg);
+            if (tracking.long == .none) tracking.long = tracking.short;
             tracking.short = switch (remaining_reg) {
                 .none => .{ .dead = function.scope_generation },
                 else => .{ .register = remaining_reg },
diff --git a/test/behavior/slice.zig b/test/behavior/slice.zig
index aa6ec9db80..22031fe698 100644
--- a/test/behavior/slice.zig
+++ b/test/behavior/slice.zig
@@ -1079,3 +1079,17 @@ test "sentinel expression in slice operation has result type" {
     comptime assert(slice[0] == 1);
     comptime assert(slice[1] == 2);
 }
+
+test "conditionally return second argument slice" {
+    if (builtin.zig_backend == .stage2_spirv) return error.SkipZigTest;
+
+    const S = struct {
+        fn foo(cond: bool, slice: []const u8) []const u8 {
+            if (cond) return slice;
+            return &.{};
+        }
+    };
+
+    try expectEqualStrings("", S.foo(false, "false"));
+    try expectEqualStrings("true", S.foo(true, "true"));
+}