RHI renderer: fix crash in Renderer::sendShaderChangesToFrontend()

The Shaders or the QShaderProgramBuilders may not exist in the managers
anymore by the time we arrive in
Renderer::sendShaderChangesToFrontend(). This happens when Qt3D shuts
down.

To fix this, check the returned values by the managers.

This is similar to the existing patch for the OpenGL renderer:
Ia021cd8f22ceb2626a7a2734b7e346fbcc8e0301

Pick-to: 6.4
Change-Id: I322bf2524016c1f98433891ad230b65272fabbdd
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/plugins/renderers/rhi/renderer/renderer.cpp b/src/plugins/renderers/rhi/renderer/renderer.cpp
index 52eca7568..66b40c21c 100644
--- a/src/plugins/renderers/rhi/renderer/renderer.cpp
+++ b/src/plugins/renderers/rhi/renderer/renderer.cpp
@@ -1528,6 +1528,9 @@ void Renderer::sendShaderChangesToFrontend(Qt3DCore::QAspectManager *manager)
     const std::vector<HShader> &activeShaders = m_nodesManager->shaderManager()->activeHandles();
     for (const HShader &handle : activeShaders) {
         Shader *s = m_nodesManager->shaderManager()->data(handle);
+        if (!s)
+            continue;
+
         if (s->requiresFrontendSync()) {
             QShaderProgram *frontend =
                     static_cast<decltype(frontend)>(manager->lookupNode(s->peerId()));
@@ -1545,6 +1548,9 @@ void Renderer::sendShaderChangesToFrontend(Qt3DCore::QAspectManager *manager)
     for (const ShaderBuilderUpdate &update : m_shaderBuilderUpdates) {
         QShaderProgramBuilder *builder =
                 static_cast<decltype(builder)>(manager->lookupNode(update.builderId));
+        if (!builder)
+            continue;
+
         QShaderProgramBuilderPrivate *dBuilder =
                 static_cast<decltype(dBuilder)>(QNodePrivate::get(builder));
         dBuilder->setShaderCode(update.shaderCode, update.shaderType);