diff --git a/include/ruby/internal/intern/proc.h b/include/ruby/internal/intern/proc.h
index 24336a6a66..d6f77cbd4d 100644
--- a/include/ruby/internal/intern/proc.h
+++ b/include/ruby/internal/intern/proc.h
@@ -46,7 +46,6 @@ VALUE rb_method_call_with_block(int, const VALUE *, VALUE, VALUE);
 VALUE rb_method_call_with_block_kw(int, const VALUE *, VALUE, VALUE, int);
 int rb_mod_method_arity(VALUE, ID);
 int rb_obj_method_arity(VALUE, ID);
-VALUE rb_callable_receiver(VALUE);
 VALUE rb_protect(VALUE (*)(VALUE), VALUE, int*);
 
 RBIMPL_SYMBOL_EXPORT_END()
diff --git a/internal/proc.h b/internal/proc.h
index 3d4c611584..5628a1f1c7 100644
--- a/internal/proc.h
+++ b/internal/proc.h
@@ -21,6 +21,7 @@ int rb_block_pair_yield_optimizable(void);
 int rb_block_arity(void);
 int rb_block_min_max_arity(int *max);
 VALUE rb_block_to_s(VALUE self, const struct rb_block *block, const char *additional_info);
+VALUE rb_callable_receiver(VALUE);
 
 MJIT_SYMBOL_EXPORT_BEGIN
 VALUE rb_func_proc_new(rb_block_call_func_t func, VALUE val);
diff --git a/proc.c b/proc.c
index 96c84d20a8..b6285b18c2 100644
--- a/proc.c
+++ b/proc.c
@@ -2740,13 +2740,16 @@ rb_obj_method_arity(VALUE obj, ID id)
 }
 
 VALUE
-rb_callable_receiver(VALUE callable) {
+rb_callable_receiver(VALUE callable)
+{
     if (rb_obj_is_proc(callable)) {
         VALUE binding = rb_funcall(callable, rb_intern("binding"), 0);
         return rb_funcall(binding, rb_intern("receiver"), 0);
-    } else if (rb_obj_is_method(callable)) {
+    }
+    else if (rb_obj_is_method(callable)) {
         return method_receiver(callable);
-    } else {
+    }
+    else {
         return Qundef;
     }
 }