QSGBatchRenderer: look for ShaderManager by type only, ignore name

There's only ever one of them, and accessing objectName() from a
different than the owning thread is UB (data race).

The default-constructed QString() is needed, cf. QTBUG-103986.

This is a hotfix for QTBUG-102403, which ran afoul of the guards added
in qtbase/3f32dcd1ddcbe04c77ccd83e2eaa566d7212e732 to fix QTBUG-99775.

Task-number: QTBUG-102403
Change-Id: Idf07b1119ec393e7fd179e8b545cfeb70f5916ec
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
(cherry picked from commit 543806e96da237a4625b593ed773813e0cdfe3fb)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp b/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
index b1565899fb..d61b7e49da 100644
--- a/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
+++ b/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
@@ -900,7 +900,7 @@ Renderer::Renderer(QSGDefaultRenderContext *ctx, QSGRendererInterface::RenderMod
     // The shader manager is shared between renderers (think for example Item
     // layers that create a new Renderer each) with the same rendercontext (and
     // so same QRhi).
-    m_shaderManager = ctx->findChild<ShaderManager *>(QStringLiteral("__qt_ShaderManager"), Qt::FindDirectChildrenOnly);
+    m_shaderManager = ctx->findChild<ShaderManager *>(QString(), Qt::FindDirectChildrenOnly);
     if (!m_shaderManager) {
         m_shaderManager = new ShaderManager(ctx);
         m_shaderManager->setObjectName(QStringLiteral("__qt_ShaderManager"));