diff --git a/CMakeLists.txt b/CMakeLists.txt
index 44ff9a13..d7c6302c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -120,14 +120,14 @@ endif()
 
 option(SIMGEAR_HEADLESS "Set to ON to build SimGear without GUI/graphics support" OFF)
 option(ENABLE_RTI       "Set to ON to build SimGear with RTI support" OFF)
-option(ENABLE_GDAL      "Set to ON to build SimGear with GDAL support" ON)
+option(ENABLE_GDAL      "Set to ON to build SimGear with GDAL support" OFF)
 option(ENABLE_TESTS     "Set to OFF to disable building SimGear's test applications" ON)
 option(ENABLE_SOUND     "Set to OFF to disable building SimGear's sound support" ON)
 option(USE_AEONWAVE     "Set to ON to use AeonWave instead of OpenAL" OFF)
 option(ENABLE_PKGUTIL   "Set to ON to build the sg_pkgutil application (default)" ON)
 option(ENABLE_DNS       "Set to ON to use udns library and DNS service resolver" ON)
 option(ENABLE_SIMD      "Enable SSE/SSE2 support for x86 compilers" ON)
-option(ENABLE_OPENMP    "Enable OpenMP compiler support" ON)
+option(ENABLE_OPENMP    "Enable OpenMP compiler support" OFF)
 
 include (DetectArch)
 
diff --git a/simgear/scene/tgdb/userdata.cxx b/simgear/scene/tgdb/userdata.cxx
index 3f81bd81..f71cb59c 100644
--- a/simgear/scene/tgdb/userdata.cxx
+++ b/simgear/scene/tgdb/userdata.cxx
@@ -64,8 +64,10 @@ simgear::ModelRegistryCallbackProxy<simgear::LoadOnlyCallback> g_stgCallbackProx
 osgDB::RegisterReaderWriterProxy<simgear::ReaderWriterSPT> g_readerWriterSPTProxy;
 simgear::ModelRegistryCallbackProxy<simgear::LoadOnlyCallback> g_sptCallbackProxy("spt");
 
+#ifdef ENABLE_GDAL
 osgDB::RegisterReaderWriterProxy<simgear::ReaderWriterPGT> g_readerWriterPGTProxy;
 simgear::ModelRegistryCallbackProxy<simgear::LoadOnlyCallback> g_pgtCallbackProxy("pgt");
+#endif
 }
 
 void sgUserDataInit( SGPropertyNode *p ) {