Fix C++23 build errors (#257)

Author: charleshofer

.bazelrc

@@ -124,6 +124,8 @@ build:clang --copt=-Wno-gnu-offsetof-extensions
 build:clang --copt=-Qunused-arguments
 # Error on struct/class mismatches, since this causes link failures on Windows.
 build:clang --copt=-Werror=mismatched-tags
+# Don't error out on C++23 extensions. Needed for building the clang-19.
+build:clang --copt=-Wno-error=c23-extensions
 
 # Configs for CUDA
 build:cuda --repo_env TF_NEED_CUDA=1