1 files changed, 40 insertions, 4 deletions
diff --git a/proc.c b/proc.c
index 95b0d04791..d3f96d703a 100644
--- a/proc.c
+++ b/proc.c
@@ -680,6 +680,29 @@ cfunc_proc_new(VALUE klass, VALUE ifunc)
     return procval;
 }
 
+VALUE
+rb_func_proc_dup(VALUE src_obj)
+{
+    RUBY_ASSERT(rb_typeddata_is_instance_of(src_obj, &proc_data_type));
+
+    rb_proc_t *src_proc;
+    GetProcPtr(src_obj, src_proc);
+    RUBY_ASSERT(vm_block_type(&src_proc->block) == block_type_ifunc);
+
+    cfunc_proc_t *proc;
+    VALUE proc_obj = TypedData_Make_Struct(rb_obj_class(src_obj), cfunc_proc_t, &proc_data_type, proc);
+
+    memcpy(&proc->basic, src_proc, sizeof(rb_proc_t));
+
+    VALUE *ep = *(VALUE **)&proc->basic.block.as.captured.ep = proc->env + VM_ENV_DATA_SIZE - 1;
+    ep[VM_ENV_DATA_INDEX_FLAGS]   = src_proc->block.as.captured.ep[VM_ENV_DATA_INDEX_FLAGS];
+    ep[VM_ENV_DATA_INDEX_ME_CREF] = src_proc->block.as.captured.ep[VM_ENV_DATA_INDEX_ME_CREF];
+    ep[VM_ENV_DATA_INDEX_SPECVAL] = src_proc->block.as.captured.ep[VM_ENV_DATA_INDEX_SPECVAL];
+    ep[VM_ENV_DATA_INDEX_ENV]     = src_proc->block.as.captured.ep[VM_ENV_DATA_INDEX_ENV];
+
+    return proc_obj;
+}
+
 static VALUE
 sym_proc_new(VALUE klass, VALUE sym)
 {
@@ -1311,12 +1334,17 @@ proc_eq(VALUE self, VALUE other)
         }
         break;
       case block_type_ifunc:
-        if (self_block->as.captured.ep != \
-                other_block->as.captured.ep ||
-                self_block->as.captured.code.ifunc != \
+        if (self_block->as.captured.code.ifunc != \
                 other_block->as.captured.code.ifunc) {
             return Qfalse;
         }
+
+        if (memcmp(
+                ((cfunc_proc_t *)self_proc)->env,
+                ((cfunc_proc_t *)other_proc)->env,
+                sizeof(((cfunc_proc_t *)self_proc)->env))) {
+            return Qfalse;
+        }
         break;
       case block_type_proc:
         if (self_block->as.proc != other_block->as.proc) {
@@ -1445,6 +1473,7 @@ rb_hash_proc(st_index_t hash, VALUE prc)
         break;
       case block_type_ifunc:
         hash = rb_st_hash_uint(hash, (st_index_t)proc->block.as.captured.code.ifunc->func);
+        hash = rb_st_hash_uint(hash, (st_index_t)proc->block.as.captured.code.ifunc->data);
         break;
       case block_type_symbol:
         hash = rb_st_hash_uint(hash, rb_any_hash(proc->block.as.symbol));
@@ -1456,7 +1485,14 @@ rb_hash_proc(st_index_t hash, VALUE prc)
         rb_bug("rb_hash_proc: unknown block type %d", vm_block_type(&proc->block));
     }
 
-    return rb_hash_uint(hash, (st_index_t)proc->block.as.captured.ep);
+    /* ifunc procs have their own allocated ep. If an ifunc is duplicated, they
+     * will point to different ep but they should return the same hash code, so
+     * we cannot include the ep in the hash. */
+    if (vm_block_type(&proc->block) != block_type_ifunc) {
+        hash = rb_hash_uint(hash, (st_index_t)proc->block.as.captured.ep);
+    }
+
+    return hash;
 }