On Fri, May 4, 2012 at 4:48 AM, Martin Jambor <mjam...@suse.cz> wrote: > Hi, > > On Thu, May 03, 2012 at 03:17:23PM -0300, Alexandre Oliva wrote: >> I've recently started getting “libstdc++-v3/include/functional:2057:63: >> internal compiler error: tree check: expected tree_vec, have error_mark >> in comp_template_args_with_info, at cp/pt.c:7038” on i686-linux-gnu, >> building libstdc++-v3/src/c++11/functexcept.cc -fPIC, at stage1 and on >> non-bootstrapped builds. The problem would not occur on >> x86_64-linux-gnu with the -m32 multilib. > > I suppose this is PR 53209. > > Thanks for dealing with this! > > Martin > >> >> Jakub reported getting similar errors in the testsuite, but not in the >> libstdc++-v3 build. >> >> Bisection revealted the patch that exposed the latent error was r186948, >> but I gather it only introduced more potentially-failing specializations >> in libstdc++-v3 at spots that wouldn't trigger the bug before. >> >> I couldn't pinpoint the exact source of randomness that causes the build >> to fail at precisely the same point on a given machine at a certain >> stage, but not on others. What I do know is that it occurs while >> iterating on a hash table, which, depending on how the hash is computed, >> may explain why we visit some nodes before others depending on >> environmentally-deterministic causes. >> >> Anyway, the problem is that, for some unsuitable candidate template >> specializations, tsubst returns error_mark_node, which tsubst_decl >> stores in argvec, and later on register_specialization gets this >> error_mark_node and tries to access it as a tree_vec. >> >> The trivial patch that avoids the misbehavior is returning >> error_mark_node as soon as we get that for argvec. Bootstrapped on >> i686-pc-linux-gnu and x86_64-linux-gnu, regstrapped on the latter. >> >> Ok to install? >> > >> for gcc/cp/ChangeLog >> from Alexandre Oliva <aol...@redhat.com> >> >> * pt.c (tsubst_decl): Bail out if argvec is error_mark_node. >> >> Index: gcc/cp/pt.c >> =================================================================== >> --- gcc/cp/pt.c.orig 2012-04-30 15:34:44.018432544 -0300 >> +++ gcc/cp/pt.c 2012-04-30 15:34:47.988375071 -0300 >> @@ -10626,6 +10626,8 @@ tsubst_decl (tree t, tree args, tsubst_f >> tmpl = DECL_TI_TEMPLATE (t); >> gen_tmpl = most_general_template (tmpl); >> argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl); >> + if (argvec == error_mark_node) >> + RETURN (error_mark_node); >> hash = hash_tmpl_and_args (gen_tmpl, argvec); >> spec = retrieve_specialization (gen_tmpl, argvec, hash); >> } >
This does fix: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53209 Can someone review it? Thanks. -- H.J.
