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* [Bug c++/113274] New: Memoization in template parameters is overly aggressive; false memoization for const pointers
@ 2024-01-08 14:50 janschultke at googlemail dot com
2024-01-08 15:01 ` [Bug c++/113274] " janschultke at googlemail dot com
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: janschultke at googlemail dot com @ 2024-01-08 14:50 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113274
Bug ID: 113274
Summary: Memoization in template parameters is overly
aggressive; false memoization for const pointers
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: janschultke at googlemail dot com
Target Milestone: ---
## Minimal Reproducible Example (https://godbolt.org/z/Y7Kr9o546)
template <auto>
struct A {
static constexpr bool value = false;
};
template <auto p>
requires __is_same(decltype(p), int*)
struct A<p> {
static constexpr bool value = false;
};
int x = 0;
//static_assert( A<&x>::value );
static_assert( A<const_cast<const int*>(&x)>::value == false );
## Explanation
Uncommenting the first static_assert causes compilation failure of the second
static_assert.
This should definitely not happen, as the following instantiations should be
distinct:
- A<(int*) &x>
- A<(const int*) &x>
GCC aggressively memoizes the first instantiation in A<&x>, which results in
the subsequent A<(const int*)&x>::value being identical, even though it should
not be.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/113274] Memoization in template parameters is overly aggressive; false memoization for const pointers
2024-01-08 14:50 [Bug c++/113274] New: Memoization in template parameters is overly aggressive; false memoization for const pointers janschultke at googlemail dot com
@ 2024-01-08 15:01 ` janschultke at googlemail dot com
2024-01-08 15:09 ` janschultke at googlemail dot com
2024-01-08 15:52 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: janschultke at googlemail dot com @ 2024-01-08 15:01 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113274
--- Comment #1 from Jan Schultke <janschultke at googlemail dot com> ---
Original problem and more discussion:
https://stackoverflow.com/q/77774976/5740428
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/113274] Memoization in template parameters is overly aggressive; false memoization for const pointers
2024-01-08 14:50 [Bug c++/113274] New: Memoization in template parameters is overly aggressive; false memoization for const pointers janschultke at googlemail dot com
2024-01-08 15:01 ` [Bug c++/113274] " janschultke at googlemail dot com
@ 2024-01-08 15:09 ` janschultke at googlemail dot com
2024-01-08 15:52 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: janschultke at googlemail dot com @ 2024-01-08 15:09 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113274
--- Comment #2 from Jan Schultke <janschultke at googlemail dot com> ---
OOPS, I've messed up the repro. It should be true in the partial
specialization.
https://godbolt.org/z/11dW3cTfc
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/113274] Memoization in template parameters is overly aggressive; false memoization for const pointers
2024-01-08 14:50 [Bug c++/113274] New: Memoization in template parameters is overly aggressive; false memoization for const pointers janschultke at googlemail dot com
2024-01-08 15:01 ` [Bug c++/113274] " janschultke at googlemail dot com
2024-01-08 15:09 ` janschultke at googlemail dot com
@ 2024-01-08 15:52 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-01-08 15:52 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113274
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |DUPLICATE
Status|UNCONFIRMED |RESOLVED
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 113272.
*** This bug has been marked as a duplicate of bug 113272 ***
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2024-01-08 15:52 UTC | newest]
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2024-01-08 14:50 [Bug c++/113274] New: Memoization in template parameters is overly aggressive; false memoization for const pointers janschultke at googlemail dot com
2024-01-08 15:01 ` [Bug c++/113274] " janschultke at googlemail dot com
2024-01-08 15:09 ` janschultke at googlemail dot com
2024-01-08 15:52 ` pinskia at gcc dot gnu.org
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