[Bug c++/109752] [ICE] in check_complete_insertion, at hash-table.h:578

["redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109752

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |aoliva at gcc dot gnu.org

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Bisection using the original preprocessed code shows it started to ICE with
r13-4937 although maybe that just added an assertion to catch a latent bug.

check hash table insertions

I've noticed a number of potential problems in hash tables, of three
kinds: insertion of entries that seem empty, dangling insertions, and
lookups during insertions.

These problems may all have the effect of replacing a deleted entry
with one that seems empty, which may disconnect double-hashing chains
involving that entry, and thus cause entries to go missing.

This patch detects such problems by recording a pending insertion and
checking that it's completed before other potentially-conflicting
operations.  The additional field is only introduced when checking is
enabled.

for  gcc/ChnageLog

* hash-table.h (check_complete_insertion, check_insert_slot):
New hash_table methods.
(m_inserting_slot): New hash_table field.
(begin, hash_table ctors, ~hash_table): Check previous insert.
(expand, empty_slow, clear_slot, find_with_hash): Likewise.
(remote_elt_with_hash, traverse_noresize): Likewise.
(gt_pch_nx): Likewise.
(find_slot_with_hash): Likewise.  Record requested insert.