diff --git a/vulkan/scripts/driver_generator.py b/vulkan/scripts/driver_generator.py
index 0be0491..0f3d760 100644
--- a/vulkan/scripts/driver_generator.py
+++ b/vulkan/scripts/driver_generator.py
@@ -272,7 +272,7 @@
   if _need_proc_hook_stub(cmd):
     return_type = gencom.return_type_dict[cmd]
     ext_name = gencom.extension_dict[cmd]
-    ext_hook = 'ProcHook::' + ext_name[3:]
+    ext_hook = 'ProcHook::' + gencom.base_ext_name(ext_name)
     handle = gencom.param_dict[cmd][0][1]
     param_types = ', '.join([''.join(i) for i in gencom.param_dict[cmd]])
     param_names = ', '.join([''.join(i[1]) for i in gencom.param_dict[cmd]])
@@ -327,7 +327,8 @@
 
   if cmd in gencom.extension_dict:
     ext_name = gencom.extension_dict[cmd]
-    f.write(gencom.indent(2) + 'ProcHook::' + ext_name[3:] + ',\n')
+    f.write(gencom.indent(2) + 'ProcHook::' +
+            gencom.base_ext_name(ext_name) + ',\n')
 
     if gencom.is_extension_internal(ext_name):
       f.write("""\
@@ -359,7 +360,8 @@
 
   if cmd in gencom.extension_dict:
     ext_name = gencom.extension_dict[cmd]
-    f.write(gencom.indent(2) + 'ProcHook::' + ext_name[3:] + ',\n')
+    f.write(gencom.indent(2) + 'ProcHook::' +
+            gencom.base_ext_name(ext_name) + ',\n')
 
     if gencom.is_extension_internal(ext_name):
       f.write("""\
diff --git a/vulkan/scripts/generator_common.py b/vulkan/scripts/generator_common.py
index 5bfa9ec..670ba66 100644
--- a/vulkan/scripts/generator_common.py
+++ b/vulkan/scripts/generator_common.py
@@ -286,7 +286,7 @@
   """
   f.write(indent(1))
   if name in extension_dict:
-    f.write('INIT_PROC_EXT(' + extension_dict[name][3:] + ', ')
+    f.write('INIT_PROC_EXT(' + base_ext_name(extension_dict[name]) + ', ')
   else:
     f.write('INIT_PROC(')