Index: setup.py
--- setup.py.orig
+++ setup.py
@@ -82,9 +82,6 @@ if not any(arg in sys.argv for arg in ['clean', 'check
         compiler_directives = {}
         if 'CYTHON_TRACE' in sys.argv:
             compiler_directives['linetrace'] = True
-        # Set CFLAG to all optimizations (-O3), add `-g0` to reduce size of binaries, see #2276
-        # Any additional CFLAGS will be appended. Only the last optimization flag will have effect
-        os.environ['CFLAGS'] = '-O3 -g0 ' + os.environ.get('CFLAGS', '')
         ext_modules = cythonize(
             'pydantic/*.py',
             exclude=['pydantic/generics.py'],