https://gcc.gnu.org/g:80e5be0c7f388cf8b8b321dca436ff529ac76867
commit r15-5048-g80e5be0c7f388cf8b8b321dca436ff529ac76867
Author: Jakub Jelinek <ja...@redhat.com>
Date: Fri Nov 8 22:07:33 2024 +0100
ibstdc++: Add some further attributes to ::operator new in <new>
I've noticed alloc_align attribute is missing on the non-vector
::operator new with std::align_val_t and const std::nothrow_t&
arguments, this patch adds it. The last hunk is just
an attempt to make the line shorter.
The first hunk originally added also __alloc_size__ (1) attribute,
but seems that regresses
FAIL: g++.dg/tm/pr46270.C -std=gnu++98 (test for excess errors)
with
Excess errors:
.../libstdc++-v3/libsupc++/new:137:26: warning: new declaration 'void*
operator new(std::size_t)' ambiguates built-in declaration 'void* operator
new(long unsigned int)
+transaction_safe' [-Wbuiltin-declaration-mismatch]
.../libstdc++-v3/libsupc++/new:140:26: warning: new declaration 'void*
operator new [](std::size_t)' ambiguates built-in declaration 'void* operator
new [](long unsigned int)
+transaction_safe' [-Wbuiltin-declaration-mismatch]
I must say I have no clue why that happens only in C++98 (C++11 and
above are quiet) and why only with -fgnu-tm, tried to debug that but
am lost. It is some conflict with the predeclared ::operator new, but
those clearly do have the externally_visible attribute, and alloc_size (1)
attributes:
extvisattr = build_tree_list (get_identifier ("externally_visible"),
NULL_TREE);
newattrs = tree_cons (get_identifier ("alloc_size"),
build_tree_list (NULL_TREE, integer_one_node),
extvisattr);
newtype = cp_build_type_attribute_variant (ptr_ftype_sizetype,
newattrs);
newtype = build_exception_variant (newtype, new_eh_spec);
...
tree opnew = push_cp_library_fn (NEW_EXPR, newtype, 0);
DECL_IS_MALLOC (opnew) = 1;
DECL_SET_IS_OPERATOR_NEW (opnew, true);
DECL_IS_REPLACEABLE_OPERATOR (opnew) = 1;
and at C++98 I think libstdc++ doesn't add transaction_safe attribute:
// Conditionally enable annotations for the Transactional Memory TS on
C++11.
// Most of the following conditions are due to limitations in the current
// implementation.
#if __cplusplus >= 201103L && _GLIBCXX_USE_CXX11_ABI \
&& _GLIBCXX_USE_DUAL_ABI && __cpp_transactional_memory >= 201500L \
&& !_GLIBCXX_FULLY_DYNAMIC_STRING && _GLIBCXX_USE_WEAK_REF \
&& _GLIBCXX_USE_ALLOCATOR_NEW
#define _GLIBCXX_TXN_SAFE transaction_safe
#define _GLIBCXX_TXN_SAFE_DYN transaction_safe_dynamic
#else
#define _GLIBCXX_TXN_SAFE
#define _GLIBCXX_TXN_SAFE_DYN
#endif
push_cp_library_fn adds transaction_safe attribute whenever -fgnu-tm
is used, regardless of the other conditionals:
if (flag_tm)
apply_tm_attr (fn, get_identifier ("transaction_safe"));
Anyway, omitting alloc_size (1) fixes that test and given that the
predeclared operator new already has alloc_size (1) attribute, I think it
can be safely left out.
2024-11-08 Jakub Jelinek <ja...@redhat.com>
* libsupc++/new (::operator new, ::operator new[]): Add malloc
attribute where missing. Add alloc_align attribute when
std::align_val_t is present and where it was missing. Formatting
fix.
Diff:
---
libstdc++-v3/libsupc++/new | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/libstdc++-v3/libsupc++/new b/libstdc++-v3/libsupc++/new
index 4345030071bb..8f8eaf9c3903 100644
--- a/libstdc++-v3/libsupc++/new
+++ b/libstdc++-v3/libsupc++/new
@@ -136,10 +136,10 @@ namespace std
*/
_GLIBCXX_NODISCARD void* operator new(std::size_t)
_GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
- __attribute__((__externally_visible__));
+ __attribute__((__externally_visible__, __malloc__));
_GLIBCXX_NODISCARD void* operator new[](std::size_t)
_GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
- __attribute__((__externally_visible__));
+ __attribute__((__externally_visible__, __malloc__));
void operator delete(void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void operator delete[](void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
@@ -169,8 +169,8 @@ _GLIBCXX_NODISCARD void* operator new(std::size_t,
std::align_val_t)
_GLIBCXX_TXN_SAFE
__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__
(2), __malloc__));
_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const
std::nothrow_t&)
- _GLIBCXX_TXN_SAFE
- _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__
(1), __malloc__));
+ _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
+ __attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__
(2), __malloc__));
void operator delete(void*, std::align_val_t) _GLIBCXX_TXN_SAFE
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete(void*, std::align_val_t, const std::nothrow_t&)
@@ -180,8 +180,8 @@ _GLIBCXX_NODISCARD void* operator new[](std::size_t,
std::align_val_t)
_GLIBCXX_TXN_SAFE
__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__
(2), __malloc__));
_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const
std::nothrow_t&)
- _GLIBCXX_TXN_SAFE
- _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__
(1), __alloc_align__ (2), __malloc__));
+ _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
+ __attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__
(2), __malloc__));
void operator delete[](void*, std::align_val_t) _GLIBCXX_TXN_SAFE
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete[](void*, std::align_val_t, const std::nothrow_t&)
