diff --git a/Makefile b/Makefile
index 7c4a0a8..e99ff19 100644
--- a/Makefile
+++ b/Makefile
@@ -367,7 +367,7 @@ ecdsa-wasm:
 bin/emu:
 	$(CXX) -g -o $@ src/fp.cpp src/bn_c256.cpp test/bn_c256_test.cpp -DMCL_DONT_USE_XBYAK -DMCL_DONT_USE_OPENSSL -DMCL_USE_VINT -DMCL_SIZEOF_UNIT=8 -DMCL_VINT_64BIT_PORTABLE -DMCL_VINT_FIXED_BUFFER -DMCL_MAX_BIT_SIZE=256 -I./include
 bin/pairing_c_min.exe: sample/pairing_c.c include/mcl/vint.hpp src/fp.cpp include/mcl/bn.hpp
-	$(CXX) -o $@ sample/pairing_c.c src/fp.cpp src/bn_c256.cpp -O3 -g -I./include -fno-threadsafe-statics -DMCL_DONT_USE_XBYAK -DMCL_DONT_USE_OPENSSL -DMCL_USE_VINT -DMCL_SIZEOF_UNIT=8 -DMCL_VINT_FIXED_BUFFER -DMCL_MAX_BIT_SIZE=256 -DMCL_VINT_64BIT_PORTABLE -DCYBOZU_DONT_USE_STRING -DCYBOZU_DONT_USE_EXCEPTION -DNDEBUG # -DMCL_DONT_USE_CSPRNG
+	$(CXX) -std=c++03 -O3 -g -fno-threadsafe-statics -fno-exceptions -fno-rtti -o $@ sample/pairing_c.c src/fp.cpp src/bn_c384_256.cpp -I./include -DMCL_DONT_USE_XBYAK -DMCL_DONT_USE_OPENSSL -DMCL_USE_VINT -DMCL_SIZEOF_UNIT=8 -DMCL_VINT_FIXED_BUFFER -DMCL_MAX_BIT_SIZE=384 -DMCL_VINT_64BIT_PORTABLE -DCYBOZU_DONT_USE_STRING -DCYBOZU_DONT_USE_EXCEPTION -DNDEBUG # -DMCL_DONT_USE_CSPRNG
 
 make_tbl:
 	$(MAKE) ../bls/src/qcoeff-bn254.hpp
diff --git a/sample/pairing_c.c b/sample/pairing_c.c
index a669ec7..b174dbe 100644
--- a/sample/pairing_c.c
+++ b/sample/pairing_c.c
@@ -7,7 +7,7 @@ int g_err = 0;
 
 int main()
 {
-	char buf[1024];
+	char buf[1600];
 	const char *aStr = "123";
 	const char *bStr = "456";
 	int ret = mclBn_init(MCL_BLS12_381, MCLBN_COMPILED_TIME_VAR);
@@ -27,16 +27,16 @@ int main()
 
 	ASSERT(!mclBnG1_hashAndMapTo(&P, "this", 4));
 	ASSERT(!mclBnG2_hashAndMapTo(&Q, "that", 4));
-	mclBnG1_getStr(buf, sizeof(buf), &P, 16);
+	ASSERT(mclBnG1_getStr(buf, sizeof(buf), &P, 16));
 	printf("P = %s\n", buf);
-	mclBnG2_getStr(buf, sizeof(buf), &Q, 16);
+	ASSERT(mclBnG2_getStr(buf, sizeof(buf), &Q, 16));
 	printf("Q = %s\n", buf);
 
 	mclBnG1_mul(&aP, &P, &a);
 	mclBnG2_mul(&bQ, &Q, &b);
 
 	mclBn_pairing(&e, &P, &Q);
-	mclBnGT_getStr(buf, sizeof(buf), &e, 16);
+	ASSERT(mclBnGT_getStr(buf, sizeof(buf), &e, 16));
 	printf("e = %s\n", buf);
 	mclBnGT_pow(&e1, &e, &a);
 	mclBn_pairing(&e2, &aP, &Q);