diff --git a/packages/sda/package.py b/packages/sda/package.py
index ee1a09290c2476efbb9a799163d2490d5c6b2fb6..1f4ea1c0d01db6be9f92ce60f4b39fe674b28b04 100644
--- a/packages/sda/package.py
+++ b/packages/sda/package.py
@@ -29,6 +29,7 @@ class Sda(MakefilePackage):
     # Dependencies.
     depends_on('%gcc@9.4.0:')
     depends_on('python@3.8:', type=('build','run'))
+    conflicts('%gcc@:9.3.999', when='@7.3.3d')
     conflicts('%intel')
 
     build_directory = 'src'