gcc default

Author: DmitriyMusatkin

builder/core/data.py

@@ -572,6 +572,7 @@ class PKG_TOOLS(Enum):
         'yum_compiler_packages': ['gcc', 'gcc-c++'],
 
         'versions': {
+            'default': {},
             '4.8': {
                 # ASan has been broken on 4.8 GCC version distributed on Ubuntu
                 # and will unlikely to get fixed upstream. so turn it off.