Avoid 'possible loss of data' casting in binary search
Because it may not be expected result.
example:
MODIFY
src/dump.c
src/dump.c
@@ -1036,14 +1036,16 @@ sym_name_cvar_p(const char *name, mrb_int len)
static const char*
sym_operator_name(const char *sym_name, mrb_int len)
{
- mrb_sym start, idx;
mrb_sym table_size = sizeof(operator_table)/sizeof(struct operator_symbol);
+ if (operator_table[table_size-1].sym_name_len < len) return NULL;
+
+ mrb_sym start, idx;
int cmp;
const struct operator_symbol *op_sym;
for (start = 0; table_size != 0; table_size/=2) {
idx = start+table_size/2;
op_sym = &operator_table[idx];
- cmp = (int)(len-op_sym->sym_name_len);
+ cmp = (int)len-(int)op_sym->sym_name_len;
if (cmp == 0) {
cmp = memcmp(sym_name, op_sym->sym_name, len);
if (cmp == 0) return op_sym->name;

MODIFY
src/symbol.c
src/symbol.c
@@ -31,11 +31,13 @@ static const struct {
static mrb_sym
presym_find(const char *name, size_t len)
{
+ if (presym_table[MRB_PRESYM_MAX-1].len < len) return 0;
+
mrb_sym start, idx, presym_size = MRB_PRESYM_MAX;
int cmp;
for (start = 0; presym_size != 0; presym_size/=2) {
idx = start+presym_size/2;
- cmp = (int)(len-presym_table[idx].len);
+ cmp = (int)len-(int)presym_table[idx].len;
if (cmp == 0) {
cmp = memcmp(name, presym_table[idx].name, len);
if (cmp == 0) return idx+1;

Avoid 'possible loss of data' casting in binary search

Because it may not be expected result.
example: https://wandbox.org/permlink/F5Mp7IEJ1VY3CFLp