fuzz: Use main from libfuzzer (#2069)

Makefile.am

 tests_fuzzing_synth_fuzzer_test_SOURCES = tests/fuzzing/synth_fuzzer.c
 tests_fuzzing_synth_fuzzer_test_LDADD =  src/libespeak-ng.la
 tests_fuzzing_synth_fuzzer_test_CFLAGS=  ${AM_CFLAGS} -DPATH_ESPEAK_DATA=\"$(abs_top_srcdir)/espeak-ng-data\" -Isrc/libespeak-ng
-tests_fuzzing_synth_fuzzer_test_LDFLAGS= ${AM_LDFLAGS} -static -lm -Wl,-z,relro ${PCAUDIOLIB_LIBS} ${LIBFUZZER_NO_MAIN}
+tests_fuzzing_synth_fuzzer_test_LDFLAGS= ${AM_LDFLAGS} -static -lm -Wl,-z,relro ${PCAUDIOLIB_LIBS} ${LIBFUZZER}
+tests_ssml_fuzzer_test_LDFLAGS = ${AM_LDFLAGS} ${LIBFUZZER}
 else
 tests_ssml_fuzzer_test_LDADD += tests/libfuzzrunner.la
 endif

configure.ac

 	TEMP_LIBS="$LIBS"
 	HOST_CPU="`$CC -print-target-triple | sed -e 's/-.*//'`"
 	LIBFUZZER_NO_MAIN="`$CC -print-file-name=libclang_rt.fuzzer_no_main-$HOST_CPU.a` -lstdc++ -lm"
+	LIBFUZZER="`$CC -print-file-name=libclang_rt.fuzzer-$HOST_CPU.a` -lstdc++ -lm"
 	CFLAGS="$CFLAGS -fsanitize=fuzzer-no-link"
 	LIBS="$LIBS $LIBFUZZER_NO_MAIN"
 	AC_MSG_CHECKING([if $CC supports fuzzer with the -fsanitize=fuzzer flag])
 	if test "$have_fuzzer_fuzzer" != yes ; then
 		CFLAGS="$TEMP_CFLAGS"
 		LIBFUZZER_NO_MAIN=""
+		LIBFUZZER=""
 	fi
 	AC_SUBST(LIBFUZZER_NO_MAIN)
+	AC_SUBST(LIBFUZZER)
 	LIBS="$TEMP_LIBS"
 	AC_LANG_POP(C)
 fi

tests/fuzzing/synth_fuzzer.c

 }
 
 /* See http://llvm.org/docs/LibFuzzer.html */
-extern int LLVMFuzzerRunDriver(int *argc, char ***argv,
-                  int (*UserCb)(const uint8_t *Data, size_t Size));
 extern int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 
 	return 0;
 }
-
-int main(int argc, char *argv[]) {
-	LLVMFuzzerRunDriver(&argc, &argv, LLVMFuzzerTestOneInput);
-}