Exclude fuzz test from non-Clang compilers.

cmake/make_cmakelists.py

@@ -214,6 +214,12 @@ class WorkspaceFileFunctions(object):
   def upb_deps(self):
     pass
 
+  def rules_fuzzing_dependencies(self):
+    pass
+
+  def rules_fuzzing_init(self):
+    pass
+
 
 class Converter(object):
   def __init__(self):

tests/BUILD

@@ -140,6 +140,11 @@ cc_test(
 )
 
 # OSS-Fuzz test
+config_setting(
+    name = "is_clang",
+    flag_values = {"@bazel_tools//tools/cpp:compiler": "clang"},
+)
+
 cc_fuzz_test(
     name = "file_descriptor_parsenew_fuzzer",
     srcs = ["file_descriptor_parsenew_fuzzer.cc"],
@@ -147,6 +152,10 @@ cc_fuzz_test(
         "//:descriptor_upb_proto",
         "//:upb",
     ],
+    target_compatible_with = select({
+        ":is_clang": [],
+        "//conditions:default": ["@platforms//:incompatible"]
+    }),
 )
 
 upb_proto_library(