Add `mrb_alloca` again; ref #4470

This time, the allocated memory comes from the string object, which is
referenced from GC arena. The memory region will be reclaimed when the C
function called from VM is terminated, or the GC arena is restored.

1 files changed, 2 insertions, 0 deletions

diff --git a/include/mruby.h b/include/mruby.h
index 5d5c759dd..3ef399716 100644
--- a/include/mruby.h
+++ b/include/mruby.h
@@ -1246,6 +1246,8 @@ MRB_API void mrb_pool_close(struct mrb_pool*);
 MRB_API void* mrb_pool_alloc(struct mrb_pool*, size_t);
 MRB_API void* mrb_pool_realloc(struct mrb_pool*, void*, size_t oldlen, size_t newlen);
 MRB_API mrb_bool mrb_pool_can_realloc(struct mrb_pool*, void*, size_t);
+/* temporary memory allocation, only effective while GC arena is kept */
+MRB_API void* mrb_alloca(mrb_state *mrb, size_t);
 
 MRB_API void mrb_state_atexit(mrb_state *mrb, mrb_atexit_func func);