Conmpile open62541 with SlapOS's gcc.

component/open62541/buildout.cfg

 # Implementation of OPC UA (OPC Unified Architecture). https://open62541.org/
 
 [buildout]
-parts = open62541
+parts =
+  open62541
+  gcc-10.2
 extends =
   ../cmake/buildout.cfg
   ../patch/buildout.cfg
   ../python3/buildout.cfg
+  ../gcc/buildout.cfg
   ../defaults.cfg
 
 [gcc]
@@ -35,4 +38,4 @@ configure-options =
 post-install =
   cp src/pubsub/*.h deps/open62541_queue.h @@LOCATION@@/include
 environment =
-  PATH=${python3:location}/bin:${patch:location}/bin:%(PATH)s
+  PATH=${gcc-10.2:location}/bin:${python3:location}/bin:${patch:location}/bin:%(PATH)s