diff --git a/build_g_32.sh b/build_g_32.sh
new file mode 100644
index 00000000..02694296
--- /dev/null
+++ b/build_g_32.sh
@@ -0,0 +1,17 @@
+set -e
+
+python prebuild.py
+
+SRC=$(find src/ -name "*.c")
+
+FLAGS="-std=c11 -lm -ldl -I3rd/lz4 -Iinclude -O0 -Wfatal-errors -g -DDEBUG -DPK_ENABLE_OS=1 -DPK_BUILD_MODULE_LZ4=1"
+
+SANITIZE_FLAGS="-fsanitize=address,leak,undefined"
+
+if [ "$(uname)" == "Darwin" ]; then
+    SANITIZE_FLAGS="-fsanitize=address,undefined"
+fi
+
+echo "Compiling C files..."
+gcc -m32 $FLAGS $SANITIZE_FLAGS $SRC src2/main.c 3rd/lz4/lz4libs/lz4.c -o main
+
diff --git a/src/common/vector.c b/src/common/vector.c
index 383bf8b5..af2b2451 100644
--- a/src/common/vector.c
+++ b/src/common/vector.c
@@ -2,59 +2,58 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include "pocketpy/common/utils.h"
 
-
-void c11_vector__ctor(c11_vector* self, int elem_size){
+void c11_vector__ctor(c11_vector* self, int elem_size) {
     self->data = NULL;
     self->length = 0;
     self->capacity = 0;
     self->elem_size = elem_size;
 }
 
-void c11_vector__dtor(c11_vector* self){
+void c11_vector__dtor(c11_vector* self) {
     if(self->data) free(self->data);
     self->data = NULL;
     self->length = 0;
     self->capacity = 0;
 }
 
-c11_vector c11_vector__copy(const c11_vector* self){
+c11_vector c11_vector__copy(const c11_vector* self) {
     c11_vector retval;
     c11_vector__ctor(&retval, self->elem_size);
     c11_vector__reserve(&retval, self->capacity);
-    memcpy(retval.data, self->data, self->elem_size * self->length);
+    memcpy(retval.data, self->data, (size_t)self->elem_size * (size_t)self->length);
     retval.length = self->length;
     return retval;
 }
 
-void c11_vector__reserve(c11_vector* self, int capacity){
+void c11_vector__reserve(c11_vector* self, int capacity) {
     if(capacity < 4) capacity = 4;
     if(capacity <= self->capacity) return;
     // self->elem_size * capacity may overflow
     self->data = realloc(self->data, (size_t)self->elem_size * (size_t)capacity);
+    if(self->data == NULL) c11__abort("c11_vector__reserve(): out of memory");
     self->capacity = capacity;
 }
 
-void c11_vector__clear(c11_vector* self){
-    self->length = 0;
-}
+void c11_vector__clear(c11_vector* self) { self->length = 0; }
 
-void* c11_vector__emplace(c11_vector* self){
-    if(self->length == self->capacity) c11_vector__reserve(self, self->capacity*2);
-    void* p = (char*)self->data + self->elem_size * self->length;
+void* c11_vector__emplace(c11_vector* self) {
+    if(self->length == self->capacity) c11_vector__reserve(self, self->capacity * 2);
+    void* p = (char*)self->data + (size_t)self->elem_size * (size_t)self->length;
     self->length++;
     return p;
 }
 
-bool c11_vector__contains(const c11_vector *self, void *elem){
-    for(int i = 0; i < self->length; i++){
-        void* p = (char*)self->data + self->elem_size * i;
+bool c11_vector__contains(const c11_vector* self, void* elem) {
+    for(int i = 0; i < self->length; i++) {
+        void* p = (char*)self->data + (size_t)self->elem_size * (size_t)i;
         if(memcmp(p, elem, self->elem_size) == 0) return true;
     }
     return false;
 }
 
-void* c11_vector__submit(c11_vector* self, int* length){
+void* c11_vector__submit(c11_vector* self, int* length) {
     void* retval = self->data;
     *length = self->length;
     self->data = NULL;
diff --git a/src/modules/time.c b/src/modules/time.c
index f29c57f0..118901ba 100644
--- a/src/modules/time.c
+++ b/src/modules/time.c
@@ -14,7 +14,7 @@
         timespec_get(&tms, TIME_UTC);
     #endif
         /* seconds, multiplied with 1 billion */
-        int64_t nanos = tms.tv_sec * NANOS_PER_SEC;
+        int64_t nanos = tms.tv_sec * (int64_t)NANOS_PER_SEC;
         /* Add full nanoseconds */
         nanos += tms.tv_nsec;
         return nanos;
diff --git a/src/public/modules.c b/src/public/modules.c
index 2d2264fb..ca2fa6f3 100644
--- a/src/public/modules.c
+++ b/src/public/modules.c
@@ -455,7 +455,7 @@ static bool builtins_ord(int argc, py_Ref argv) {
 static bool builtins_id(int argc, py_Ref argv) {
     PY_CHECK_ARGC(1);
     if(argv->is_ptr) {
-        py_newint(py_retval(), (py_i64)argv->_obj);
+        py_newint(py_retval(), (intptr_t)argv->_obj);
     } else {
         py_newnone(py_retval());
     }
diff --git a/src/public/py_object.c b/src/public/py_object.c
index d9212327..a5fa0542 100644
--- a/src/public/py_object.c
+++ b/src/public/py_object.c
@@ -16,7 +16,7 @@ bool pk__object_new(int argc, py_Ref argv) {
 static bool object__hash__(int argc, py_Ref argv) {
     PY_CHECK_ARGC(1);
     assert(argv->is_ptr);
-    py_newint(py_retval(), (py_i64)argv->_obj);
+    py_newint(py_retval(), (intptr_t)argv->_obj);
     return true;
 }
 
diff --git a/tests/98_lz4.py b/tests/98_lz4.py
index 5cdb2a6e..4178aaee 100644
--- a/tests/98_lz4.py
+++ b/tests/98_lz4.py
@@ -26,6 +26,6 @@ for i in range(100):
     ratio = test(gen_data())
     # print(f'compression ratio: {ratio:.2f}')
 
-# test 100MB of random data
-rnd = [random.randint(0, 255) for _ in range(1024*1024*100)]
+# test 1GB random data
+rnd = [random.randint(0, 255) for _ in range(1024*1024*1024//16)]
 test(bytes(rnd))