diff --git a/glfw/glfw.py b/glfw/glfw.py
index 61e85f3b5..336fb2a40 100755
--- a/glfw/glfw.py
+++ b/glfw/glfw.py
@@ -90,7 +90,7 @@ def cc_version_string(self) -> str:
 
     @property
     def is_gcc(self) -> bool:
-        return 'gcc' in self.cc_version_string.split(maxsplit=1)[0]
+        return 'gcc' in self.cc_version_string.split(maxsplit=1)[0].lower()
 
     def copy(self) -> 'Env':
         ans = Env(self.cc, list(self.cppflags), list(self.cflags), list(self.ldflags), dict(self.library_paths), list(self.ldpaths), self.ccver)