From 27566fec3083d0296b26e5a5c736b0cff72aaf75 Mon Sep 17 00:00:00 2001
From: Brad Werth <werth@efn.org>
Date: Tue, 2 Sep 2025 20:32:16 +0000
Subject: [PATCH] Bug 1983838: Provide a default convertType implementation.
 r=ahale a=RyanVM

This ensures there are sane values in the dst array.

Differential Revision: https://phabricator.services.mozilla.com/D262997
---
 dom/canvas/WebGLTexelConversions.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/dom/canvas/WebGLTexelConversions.h b/dom/canvas/WebGLTexelConversions.h
index 635f3b9f728e..8b67882746ce 100644
--- a/dom/canvas/WebGLTexelConversions.h
+++ b/dom/canvas/WebGLTexelConversions.h
@@ -1345,6 +1345,11 @@ template <typename SrcType, typename DstType>
 MOZ_ALWAYS_INLINE void convertType(const SrcType* __restrict src,
                                    DstType* __restrict dst) {
   MOZ_ASSERT(false, "Unimplemented texture format conversion");
+  // Default construct dst values, ensuring they are *some* value.
+  dst[0] = DstType();
+  dst[1] = DstType();
+  dst[2] = DstType();
+  dst[3] = DstType();
 }
 
 template <>