On 2/9/22 10:51, Qing Zhao wrote:
On Feb 8, 2022, at 4:20 PM, Jason Merrill <ja...@redhat.com> wrote:
On 2/8/22 15:11, Qing Zhao wrote:
Hi,
This is the patch to fix PR101515 (ICE in pp_cxx_unqualified_id, at
cp/cxx-pretty-print.c:128)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101515
It's possible that the TYPE_NAME of a record_type is NULL, therefore when
printing the TYPE_NAME, we should check and handle this special case.
Please see the comment of pr101515 for more details.
The fix is very simple, just check and special handle cases when TYPE_NAME is
NULL.
Bootstrapped and regression tested on both x86 and aarch64, no issues.
Okay for commit?
Thanks.
Qing
=====================================
From f37ee8d21b80cb77d8108cb97a487c84c530545b Mon Sep 17 00:00:00 2001
From: Qing Zhao <qing.z...@oracle.com>
Date: Tue, 8 Feb 2022 16:10:37 +0000
Subject: [PATCH] Fix PR 101515 ICE in pp_cxx_unqualified_id, at
cp/cxx-pretty-print.c:128.
It's possible that the TYPE_NAME of a record_type is NULL, therefore when
printing the TYPE_NAME, we should check and handle this special case.
gcc/cp/ChangeLog:
* cxx-pretty-print.cc (pp_cxx_unqualified_id): Check and handle
the case when TYPE_NAME is NULL.
gcc/testsuite/ChangeLog:
* g++.dg/pr101515.C: New test.
---
gcc/cp/cxx-pretty-print.cc | 5 ++++-
gcc/testsuite/g++.dg/pr101515.C | 25 +++++++++++++++++++++++++
2 files changed, 29 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/pr101515.C
diff --git a/gcc/cp/cxx-pretty-print.cc b/gcc/cp/cxx-pretty-print.cc
index 4f9a090e520d..744ed0add5ba 100644
--- a/gcc/cp/cxx-pretty-print.cc
+++ b/gcc/cp/cxx-pretty-print.cc
@@ -171,7 +171,10 @@ pp_cxx_unqualified_id (cxx_pretty_printer *pp, tree t)
case ENUMERAL_TYPE:
case TYPENAME_TYPE:
case UNBOUND_CLASS_TEMPLATE:
- pp_cxx_unqualified_id (pp, TYPE_NAME (t));
+ if (TYPE_NAME (t))
+ pp_cxx_unqualified_id (pp, TYPE_NAME (t));
+ else
+ pp_string (pp, "<unnamed type>");
Hmm, but it's not an unnamed class, it's a pointer to member function type, and
it would be better to avoid dumping compiler internal representations like the
__pfn field name.
Yes, It’s not an unnamed class, but the ICE happened when try to print the
compiler generated member function type “__ptrmemfunc_type”, whose TYPE_NAME is
NULLed during building this type in c++ FE and the c++ FE does not handle the
case when TYPE_NAME is NULL correctly.
So, there are two levels of issues:
1. The first level issue is that the current C++ FE does not handle the case
TYPE_NAME being NULL correctly, this is indeed a bug in the current code and
should be fixed as in the current patch.
Sure, we might as well make this code more robust. But we can do better
than <unnamed type> if we check TYPE_PTRMEMFUNC_P.
2. The second level issue is what you suggested in the above, shall we print
the “compiler generated internal type” to the user? And I agree with you that
it might not be a good idea to print such compiler internal names to the user.
Are we do this right now in general? (i.e, check whether the current TYPE is a
source level TYPE or a compiler internal TYPE, and then only print out the name
of TYPE for the source level TYPE?) and is there a bit in the TYPE to
distinguish whether a TYPE is user -level type or a compiler generated internal
type?
I think the real problem comes sooner, when c_fold_indirect_ref_for_warn turns
a MEM_REF with RECORD_TYPE into a COMPONENT_REF with POINTER_TYPE.
What’s the major issue for this transformation? (I will study this in more
details).
We told c_fold_indirect_ref that we want a RECORD_TYPE (the PMF as a
whole) and it gave us back a POINTER_TYPE instead (the __pmf member).
Folding shouldn't change the type of an expression like that.
Jason
