It seems I cannot reproduce the issue. Should we drop this patch, then? Or do you think there's value in keeping it?
On Mon, 2022-06-06 at 19:01 -0400, David Malcolm wrote: > On Thu, 2022-06-02 at 21:23 -0400, Antoni Boucher via Gcc-patches > wrote: > > Sorry, forgot to attach the patch. > > > > Here it is. > > > > On Thu, 2022-06-02 at 21:20 -0400, Antoni Boucher via Jit wrote: > > > Hi. > > > The attached patch fix bug 105827: > > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105827 > > > > > > I'm not sure how to test this, so please share ideas. > > Do you have a reproducer for this? > > With garbage-collections issues in libgccjit, you can set: > > gcc_jit_context_set_bool_option (ctxt, > GCC_JIT_BOOL_OPTION_SELFCHECK_GC, > 1); > > which will force a full garbage collection at every opportunity that > the collector considers doing one (rather than following heuristics) > > This really slows things down, but makes reproducing crashes much > more > deterministic, often turning "it crashes every now and then" to "it > crashes every time" (and the test suite runs with this enabled). > > > > > > > Thanks for the review. > > > > > diff --git a/gcc/jit/dummy-frontend.cc b/gcc/jit/dummy-frontend.cc > > index 84ff359bfe3..8bb5d03d630 100644 > > --- a/gcc/jit/dummy-frontend.cc > > +++ b/gcc/jit/dummy-frontend.cc > > @@ -506,13 +506,14 @@ struct GTY(()) lang_identifier > > > > /* The resulting tree type. */ > > > > +/* See lang_tree_node in gcc/c/c-decl.cc. */ > > union GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"), > > - chain_next ("CODE_CONTAINS_STRUCT (TREE_CODE > > (&%h.generic), TS_COMMON) ? ((union lang_tree_node *) TREE_CHAIN > > (&%h.generic)) : NULL"))) > > -lang_tree_node > > -{ > > - union tree_node GTY((tag ("0"), > > - desc ("tree_node_structure (&%h)"))) > > generic; > > - struct lang_identifier GTY((tag ("1"))) identifier; > > + chain_next ("(union lang_tree_node *) jit_tree_chain_next > > (&%h.generic)"))) lang_tree_node > > + { > > + union tree_node GTY ((tag ("0"), > > + desc ("tree_node_structure (&%h)"))) > > + generic; > > + struct lang_identifier GTY ((tag ("1"))) identifier; > > }; > > Those GTY markings on gcc/jit/dummy-frontend.cc's lang_tree_node > union > have been like that since my initial proof-of-concept patch back in > 2013: > https://gcc.gnu.org/legacy-ml/gcc-patches/2013-10/msg00228.html > so presumably I simply copied and pasted that from another frontend > when I was initially prototyping libgccjit. There was an element of > "cargo cult programming" as I was getting the project started. > > Jakub had changed the C and C++ frontends in June 2011 with > 563007852e8d19b66ec8c1e42e431efaaa967dc6, which introduced the > c_tree_chain_next that you're now copying in your patch, so > presumably > I copied from a different frontend. My notes say I created the first > prototype in July 2013, so that's when I would have copied&pasted the > code. > > Dave > > > > > >
