Hi! I'd like to ping this patch:
https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607145.html - PR107558 - P2 - c++: Don't clear TREE_READONLY for -fmerge-all-constants for non-aggregates Thanks Jakub On Thu, Nov 24, 2022 at 10:13:55AM +0100, Jakub Jelinek via Gcc-patches wrote: > The following testcase ICEs, because OpenMP lowering for shared clause > on l variable with REFERENCE_TYPE creates POINTER_TYPE to REFERENCE_TYPE. > The reason is that the automatic variable has non-trivial construction > (reference to a lambda) and -fmerge-all-constants is on and so TREE_READONLY > isn't set - omp-low will handle automatic TREE_READONLY vars in shared > specially and only copy to the construct and not back, while !TREE_READONLY > are assumed to be changeable. > The PR91529 change rationale was that the gimplification can change > some non-addressable automatic variables to TREE_STATIC with > -fmerge-all-constants and therefore TREE_READONLY on them is undesirable. > But, the gimplifier does that only for aggregate variables: > switch (TREE_CODE (type)) > { > case RECORD_TYPE: > case UNION_TYPE: > case QUAL_UNION_TYPE: > case ARRAY_TYPE: > and not for anything else. So, I think clearing TREE_READONLY for > automatic integral or reference or pointer etc. vars for > -fmerge-all-constants only is unnecessary. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > 2022-11-24 Jakub Jelinek <ja...@redhat.com> > > PR c++/107558 > * decl.cc (cp_finish_decl): Don't clear TREE_READONLY on > automatic non-aggregate variables just because of > -fmerge-all-constants. > > * g++.dg/gomp/pr107558.C: New test. > > --- gcc/cp/decl.cc.jj 2022-11-19 09:21:14.662439877 +0100 > +++ gcc/cp/decl.cc 2022-11-23 13:12:31.866553152 +0100 > @@ -8679,8 +8679,10 @@ cp_finish_decl (tree decl, tree init, bo > > if (var_definition_p > /* With -fmerge-all-constants, gimplify_init_constructor > - might add TREE_STATIC to the variable. */ > - && (TREE_STATIC (decl) || flag_merge_constants >= 2)) > + might add TREE_STATIC to aggregate variables. */ > + && (TREE_STATIC (decl) > + || (flag_merge_constants >= 2 > + && AGGREGATE_TYPE_P (type)))) > { > /* If a TREE_READONLY variable needs initialization > at runtime, it is no longer readonly and we need to > --- gcc/testsuite/g++.dg/gomp/pr107558.C.jj 2022-11-23 13:13:27.260736525 > +0100 > +++ gcc/testsuite/g++.dg/gomp/pr107558.C 2022-11-23 13:15:22.271041005 > +0100 > @@ -0,0 +1,14 @@ > +// PR c++/107558 > +// { dg-do compile { target c++11 } } > +// { dg-additional-options "-fmerge-all-constants" } > +// { dg-additional-options "-flto" { target lto } } > + > +int a = 15; > + > +void > +foo () > +{ > + auto &&l = [&]() { return a; }; > +#pragma omp target parallel > + l (); > +}
