https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97342
--- Comment #2 from CVS Commits ---
The master branch has been updated by Martin Sebor :
https://gcc.gnu.org/g:83685efd5fd1623cfc4e4c435ce2773d95d458d1
commit r11-3827-g83685efd5fd1623cfc4e4c435ce2773d95d458d1
Author: Martin Sebor
Date: Fri Oct 9 14:48:43 2020 -0600
Generalize compute_objsize to return maximum size/offset instead of failing
(PR middle-end/97023).
Also resolves:
PR middle-end/97342 - bogus -Wstringop-overflow with nonzero signed and
unsigned offsets
PR middle-end/97023 - missing warning on buffer overflow in chained mempcpy
PR middle-end/96384 - bogus -Wstringop-overflow= storing into
multidimensional array with index in range
gcc/ChangeLog:
PR middle-end/97342
PR middle-end/97023
PR middle-end/96384
* builtins.c (access_ref::access_ref): Initialize new member. Use
new enum.
(access_ref::size_remaining): Define new member function.
(inform_access): Handle expressions referencing objects.
(gimple_call_alloc_size): Call get_size_range instead of get_range.
(gimple_call_return_array): New function.
(get_range): Rename...
(get_offset_range): ...to this. Improve detection of ranges from
types of expressions.
(gimple_call_return_array): Adjust calls to get_range per above.
(compute_objsize): Same. Set maximum size or offset instead of
failing for unknown objects and handle more kinds of expressions.
(compute_objsize): Call access_ref::size_remaining.
(compute_objsize): Have transitional wrapper fail for pointers
into unknown objects.
(expand_builtin_strncmp): Call access_ref::size_remaining and
handle new cases.
* builtins.h (access_ref::size_remaining): Declare new member
function.
(access_ref::set_max_size_range): Define new member function.
(access_ref::add_ofset, access_ref::add_max_ofset): Same.
(access_ref::add_base0): New data member.
* calls.c (get_size_range): Change argument type. Handle new
condition.
* calls.h (get_size_range): Adjust signature.
(enum size_range_flags): Define new type.
* gimple-ssa-warn-restrict.c (builtin_memref::builtin_memref):
Correct
argument to get_size_range.
* tree-ssa-strlen.c (get_range): Handle anti-ranges.
(maybe_warn_overflow): Check DECL_P before assuming it's one.
gcc/testsuite/ChangeLog:
PR middle-end/97342
PR middle-end/97023
PR middle-end/96384
* c-c++-common/Wrestrict.c: Adjust comment.
* gcc.dg/Wstringop-overflow-34.c: Remove xfail.
* gcc.dg/Wstringop-overflow-43.c: Remove xfails. Adjust regex
patterns.
* gcc.dg/pr51683.c: Prune out expected warning.
* gcc.target/i386/pr60693.c: Same.
* g++.dg/warn/Wplacement-new-size-8.C: New test.
* gcc.dg/Wstringop-overflow-41.c: New test.
* gcc.dg/Wstringop-overflow-44.s: New test.
* gcc.dg/Wstringop-overflow-45.c: New test.
* gcc.dg/Wstringop-overflow-46.c: New test.
* gcc.dg/Wstringop-overflow-47.c: New test.
* gcc.dg/Wstringop-overflow-49.c: New test.
* gcc.dg/Wstringop-overflow-50.c: New test.
* gcc.dg/Wstringop-overflow-51.c: New test.
* gcc.dg/Wstringop-overflow-52.c: New test.
* gcc.dg/Wstringop-overflow-53.c: New test.
* gcc.dg/Wstringop-overflow-54.c: New test.
* gcc.dg/Wstringop-overflow-55.c: New test.
* gcc.dg/Wstringop-overread-5.c: New test.
