From 18e8303d1811f9848318b4ef8831e6624fbffb2b Mon Sep 17 00:00:00 2001
From: Silvio Traversaro <silvio@traversaro.it>
Date: Mon, 27 Nov 2023 17:39:02 +0100
Subject: [PATCH] yarpviz: Support compilation with graphviz >= 9

---
 doc/release/yarp_3_9/yarpviz_graphviz9.md | 3 +++
 extern/qgv/CMakeLists.txt                 | 6 ++++++
 extern/qgv/qgv/QGVCore/private/QGVCore.h  | 2 ++
 3 files changed, 11 insertions(+)
 create mode 100644 doc/release/yarp_3_9/yarpviz_graphviz9.md

diff --git a/doc/release/yarp_3_9/yarpviz_graphviz9.md b/doc/release/yarp_3_9/yarpviz_graphviz9.md
new file mode 100644
index 00000000000..a518b09be09
--- /dev/null
+++ b/doc/release/yarp_3_9/yarpviz_graphviz9.md
@@ -0,0 +1,3 @@
+#### `yarpviz`
+
+* Support compilation with Graphviz >= 9.
diff --git a/extern/qgv/CMakeLists.txt b/extern/qgv/CMakeLists.txt
index fee2df4dd4d..571b2753f7d 100644
--- a/extern/qgv/CMakeLists.txt
+++ b/extern/qgv/CMakeLists.txt
@@ -53,6 +53,12 @@ if(Graphviz_DEFINITIONS)
   target_compile_definitions(YARP_priv_qgvcore PRIVATE ${Graphviz_DEFINITIONS})
 endif()
 
+if(Graphviz_VERSION)
+  if(Graphviz_VERSION VERSION_GREATER_EQUAL 9.0)
+    target_compile_definitions(YARP_priv_qgvcore PRIVATE GRAPHVIZ_VERSION_GE_9)
+  endif()
+endif()
+
 set_property(TARGET YARP_priv_qgvcore PROPERTY FOLDER "Libraries/External")
 
 
diff --git a/extern/qgv/qgv/QGVCore/private/QGVCore.h b/extern/qgv/qgv/QGVCore/private/QGVCore.h
index c5d47f46c04..8e5c7243c10 100644
--- a/extern/qgv/qgv/QGVCore/private/QGVCore.h
+++ b/extern/qgv/qgv/QGVCore/private/QGVCore.h
@@ -93,7 +93,9 @@ class QGVCore
         rdr.len = strlen(cp);
         rdr.cur = 0;
 
+#ifndef GRAPHVIZ_VERSION_GE_9
         disc.mem = &AgMemDisc;
+#endif
         disc.id = &AgIdDisc;
         disc.io = &memIoDisc;
         g = agread (&rdr, &disc);