From 1fac99afdae2671a9ca86bead5bde4d0e2eff1b4 Mon Sep 17 00:00:00 2001 From: Koichi Sasada Date: Wed, 31 Mar 2021 17:39:40 +0900 Subject: skip marking for uninitialized imemo_env. RUBY_INTERNAL_EVENT_NEWOBJ can expose uninitialized imemo_env objects and marking it will cause critical error. This patch skips marking on uninitialized imemo_env. See: http://rubyci.s3.amazonaws.com/centos7/ruby-master/log/20210329T183003Z.fail.html.gz Shortest repro-code is provided by mame-san. --- gc.c | 16 ++++++++++------ test/objspace/test_objspace.rb | 13 +++++++++++++ 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/gc.c b/gc.c index 8218f88d0d..a13f716d13 100644 --- a/gc.c +++ b/gc.c @@ -6266,12 +6266,16 @@ gc_mark_imemo(rb_objspace_t *objspace, VALUE obj) case imemo_env: { const rb_env_t *env = (const rb_env_t *)obj; - GC_ASSERT(env->ep[VM_ENV_DATA_INDEX_ENV] == obj); - GC_ASSERT(VM_ENV_ESCAPED_P(env->ep)); - gc_mark_values(objspace, (long)env->env_size, env->env); - VM_ENV_FLAGS_SET(env->ep, VM_ENV_FLAG_WB_REQUIRED); - gc_mark(objspace, (VALUE)rb_vm_env_prev_env(env)); - gc_mark(objspace, (VALUE)env->iseq); + + if (LIKELY(env->ep)) { + // just after newobj() can be NULL here. + GC_ASSERT(env->ep[VM_ENV_DATA_INDEX_ENV] == obj); + GC_ASSERT(VM_ENV_ESCAPED_P(env->ep)); + gc_mark_values(objspace, (long)env->env_size, env->env); + VM_ENV_FLAGS_SET(env->ep, VM_ENV_FLAG_WB_REQUIRED); + gc_mark(objspace, (VALUE)rb_vm_env_prev_env(env)); + gc_mark(objspace, (VALUE)env->iseq); + } } return; case imemo_cref: diff --git a/test/objspace/test_objspace.rb b/test/objspace/test_objspace.rb index 841a1e7c2a..1ccee02faa 100644 --- a/test/objspace/test_objspace.rb +++ b/test/objspace/test_objspace.rb @@ -243,6 +243,19 @@ class TestObjSpace < Test::Unit::TestCase GC.enable end + def test_trace_object_allocations_gc_stress + prev = GC.stress + GC.stress = true + + ObjectSpace.trace_object_allocations{ + proc{} + } + + assert true # success + ensure + GC.stress = prev + end + def test_dump_flags info = ObjectSpace.dump("foo".freeze) assert_match(/"wb_protected":true, "old":true/, info) -- cgit v1.2.3