From d97441d37ef08813187f1b44ec29612619104585 Mon Sep 17 00:00:00 2001
From: mlugg <mlugg@mlugg.co.uk>
Date: Sat, 1 Feb 2025 09:46:29 +0000
Subject: [PATCH] Sema: fix `@splat` of OPV arrays

---
 src/Sema.zig | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/Sema.zig b/src/Sema.zig
index bc9d5ea55f..caf457a989 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -24581,8 +24581,12 @@ fn zirSplat(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.I
 
     const len = try sema.usizeCast(block, src, dest_ty.arrayLen(zcu));
 
-    // `len == 0` because `[0:s]T` always has a comptime-known splat.
-    if (!dest_ty.hasRuntimeBits(zcu) or len == 0) {
+    if (try sema.typeHasOnePossibleValue(dest_ty)) |val| {
+        return Air.internedToRef(val.toIntern());
+    }
+
+    // We also need this case because `[0:s]T` is not OPV.
+    if (len == 0) {
         const empty_aggregate = try pt.intern(.{ .aggregate = .{
             .ty = dest_ty.toIntern(),
             .storage = .{ .elems = &.{} },