Remove a meaningless type cast.
Add comments for paradnoid (a.k.a. mission critical) engineers.
Use int. They are no need to use unsigned/signed long. Think about 16bit architectures.
Copy to *lenp just in case lenp != NULL.
Use mrb_int as possible.
mrb_sys_fail raises SystemCallError if we have it.
Merge branch 'master' into pr-systemcallerror
Merge branch 'master' into pr-systemcallerror
mrb_str_new2 -> mrb_str_new_cstr
set DATA_TYPE as soon as possible.
Add the type check in mrb_str_to_cstr().
Simplify. Temporary variable "i" is removed.
Extract stack zero filling to stack_clear(). Porting evelopers can optimize by replacing to memset() on their own risk.
Add null check
Cut off eval_test from main
Merge pull request #1003 from kano4/pr-add-null-check

Add null check
Merge pull request #1004 from kano4/pr-cut-off-eval_test

Cut off eval_test from main
Merge pull request #996 from iij/pr-systemcallerror

mrb_sys_fail raises an instance of (subclass of) SystemCallError if we have it
Merge pull request #1000 from iij/pr-set-data-type-asap

DATA_TYPE must be set as soon as possible
Merge pull request #1002 from monaka/pr-extract-stack-zero-filling

Extract stack zero filling into new function.