gcc/libstdc++-v3
Jonathan Wakely a634928f5c libstdc++: Fix pretty printing of std::unique_ptr [PR103086]
Since std::tuple started using [[no_unique_address]] the tuple<T*, D>
member of std::unique_ptr<T, D> has two _M_head_impl subobjects, in
different base classes. That means this printer code is ambiguous:

    tuple_head_type = tuple_impl_type.fields()[1].type   # _Head_base
    head_field = tuple_head_type.fields()[0]
    if head_field.name == '_M_head_impl':
        self.pointer = tuple_member['_M_head_impl']

In older versions of GDB it happened to work by chance, because GDB
returned the last _M_head_impl member and std::tuple's base classes are
stored in reverse order, so the last one was the T* element of the
tuple. Since GDB 11 it returns the first _M_head_impl, which is the
deleter element.

The fix is for the printer to stop using an ambiguous field name and
cast the tuple to the correct base class before accessing the
_M_head_impl member.

Instead of fixing this in both UniquePointerPrinter and StdPathPrinter a
new unique_ptr_get function is defined to do it correctly. That is
defined in terms of new tuple_get and _tuple_impl_get functions.

It would be possible to reuse _tuple_impl_get to access each element in
StdTuplePrinter._iterator.__next__, but that already does the correct
casting, and wouldn't be much simpler anyway.

libstdc++-v3/ChangeLog:

	PR libstdc++/103086
	* python/libstdcxx/v6/printers.py (_tuple_impl_get): New helper
	for accessing the tuple element stored in a _Tuple_impl node.
	(tuple_get): New function for accessing a tuple element.
	(unique_ptr_get): New function for accessing a unique_ptr.
	(UniquePointerPrinter, StdPathPrinter): Use unique_ptr_get.
	* python/libstdcxx/v6/xmethods.py (UniquePtrGetWorker): Cast
	tuple to its base class before accessing _M_head_impl.
2021-11-04 22:50:02 +00:00
..
config aix: Protect AIX math.h overloads with new macro. 2021-07-22 11:30:34 -04:00
doc libstdc++: Deprecate std::unexpected and handler functions 2021-11-04 20:53:29 +00:00
include libstdc++: Consolidate duplicate metaprogramming utilities 2021-11-04 18:14:50 +00:00
libsupc++ libstdc++: Deprecate std::unexpected and handler functions 2021-11-04 20:53:29 +00:00
po Update copyright years. 2021-01-04 10:26:59 +01:00
python libstdc++: Fix pretty printing of std::unique_ptr [PR103086] 2021-11-04 22:50:02 +00:00
scripts libstdc++: Improve generated man pages for libstdc++ 2021-10-21 22:24:57 +01:00
src libstdc++: Implement std::random_device::entropy() for other sources 2021-10-19 17:27:06 +01:00
testsuite libstdc++: Deprecate std::unexpected and handler functions 2021-11-04 20:53:29 +00:00
acinclude.m4 ctype support for libstdc++ on VxWorks 2021-05-04 21:49:43 -03:00
aclocal.m4
ChangeLog Daily bump. 2021-11-04 00:16:32 +00:00
ChangeLog-1998
ChangeLog-1999
ChangeLog-2000
ChangeLog-2001
ChangeLog-2002
ChangeLog-2003
ChangeLog-2004
ChangeLog-2005
ChangeLog-2006
ChangeLog-2007
ChangeLog-2008
ChangeLog-2009
ChangeLog-2010
ChangeLog-2011
ChangeLog-2012
ChangeLog-2013
ChangeLog-2014
ChangeLog-2015
ChangeLog-2016
ChangeLog-2017
ChangeLog-2018
ChangeLog-2019
ChangeLog-2020 libstdc++: Fix typo in ChangeLog-2020 2021-01-13 11:02:13 +00:00
config.h.in libstdc++: Use secure_getenv for filesystem::temp_directory_path() [PR65018] 2021-07-30 18:12:39 +01:00
configure libstdc++: Check for TLS support on mingw cross-compilers 2021-09-15 09:49:33 +01:00
configure.ac libstdc++: Fix broken autoconf check for O_NONBLOCK 2021-08-31 17:38:27 +01:00
configure.host Scope libstdc++ configuration for vxworks to all versions 2020-10-22 16:40:57 +00:00
crossconfig.m4 libstdc++: Check for TLS support on mingw cross-compilers 2021-09-15 09:49:33 +01:00
fragment.am libstdc++: Add C++ runtime support for new 128-bit long double format 2020-12-16 23:25:01 +00:00
linkage.m4
Makefile.am Update copyright years. 2021-01-04 10:26:59 +01:00
Makefile.in libstdc++: Add C++ runtime support for new 128-bit long double format 2020-12-16 23:25:01 +00:00
README

file: libstdc++-v3/README

New users may wish to point their web browsers to the file
index.html in the 'doc/html' subdirectory.  It contains brief
building instructions and notes on how to configure the library in
interesting ways.