Fix handling of gcc compiler default case

.github/workflows/sanity-test.yml

@@ -297,7 +297,7 @@ jobs:
         - musllinux-1-1-x64
 
     needs: package
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-22.04 # temporarily downgrade to old ubuntu as 24.04 likes to segfault in the middle of the build 
     steps:
     - uses: aws-actions/configure-aws-credentials@v4
       with:

builder/core/data.py

@@ -572,6 +572,12 @@ class PKG_TOOLS(Enum):
         'yum_compiler_packages': ['gcc', 'gcc-c++'],
 
         'versions': {
+            'default': {
+                '!c': "gcc",
+                '!cxx': "g++",
+                '!compiler_packages': [],
+                '!apt_compiler_packages': [],
+            },
             '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.