GCC modified for the FreeChainXenon project
Find a file
Patrick Palka 0a37463758 c++: partial ordering and dep alias tmpl specs [PR90679]
During partial ordering, we want to look through dependent alias
template specializations within template arguments and otherwise
treat them as opaque in other contexts (see e.g. r7-7116-g0c942f3edab108
and r11-7011-g6e0a231a4aa240).  To that end template_args_equal was
given a partial_order flag that controls this behavior.  This flag
does the right thing when a dependent alias template specialization
appears as template argument of the partial specialization, e.g. in

  template<class T, class...> using first_t = T;
  template<class T> struct traits;
  template<class T> struct traits<first_t<T, T&>> { }; // #1
  template<class T> struct traits<first_t<const T, T&>> { }; // #2

we correctly consider #2 to be more specialized than #1.  But if the
alias specialization appears as a nested template argument of another
class template specialization, e.g. in

  template<class T> struct traits<A<first_t<T, T&>>> { }; // #1
  template<class T> struct traits<A<first_t<const T, T&>>> { }; // #2

then we incorrectly consider #1 and #2 to be unordered.  This is because

  1. we don't propagate the flag to recursive template_args_equal calls
  2. we don't use structural equality for class template specializations
     written in terms of dependent alias template specializations

This patch fixes the first issue by turning the partial_order flag into
a global.  This patch fixes the second issue by making us propagate
structural equality appropriately when building a class template
specialization.  In passing this patch also improves hashing of
specializations that use structural equality.

	PR c++/90679

gcc/cp/ChangeLog:

	* cp-tree.h (comp_template_args): Remove partial_order parameter.
	(template_args_equal): Likewise.
	* pt.cc (comparing_for_partial_ordering): New global flag.
	(iterative_hash_template_arg) <case tcc_type>: Hash the template
	and arguments for specializations that use structural equality.
	(template_args_equal): Remove partial order parameter and
	use comparing_for_partial_ordering instead.
	(comp_template_args): Likewise.
	(comp_template_args_porder): Set comparing_for_partial_ordering
	instead.  Make static.
	(any_template_arguments_need_structural_equality_p): Return true
	for an argument that's a dependent alias template specialization
	or a class template specialization that itself needs structural
	equality.
	* tree.cc (cp_tree_equal) <case TREE_VEC>: Adjust call to
	comp_template_args.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/alias-decl-75a.C: New test.
	* g++.dg/cpp0x/alias-decl-75b.C: New test.
2023-12-19 11:40:15 -05:00
.github Minor formatting fix for newly-added file from previous commit 2023-11-01 19:28:56 -04:00
c++tools
config Daily bump. 2023-12-01 00:17:36 +00:00
contrib Daily bump. 2023-12-15 00:17:17 +00:00
fixincludes Daily bump. 2023-11-23 00:18:14 +00:00
gcc c++: partial ordering and dep alias tmpl specs [PR90679] 2023-12-19 11:40:15 -05:00
gnattools
gotools Daily bump. 2023-11-04 00:16:45 +00:00
include Daily bump. 2023-12-16 00:17:35 +00:00
INSTALL
libada
libatomic Daily bump. 2023-12-16 00:17:35 +00:00
libbacktrace Daily bump. 2023-12-01 00:17:36 +00:00
libcc1 Daily bump. 2023-12-07 00:17:06 +00:00
libcody
libcpp Daily bump. 2023-12-14 00:18:00 +00:00
libdecnumber
libffi Daily bump. 2023-10-27 00:17:12 +00:00
libgcc Daily bump. 2023-12-17 00:17:30 +00:00
libgfortran Daily bump. 2023-12-19 00:17:36 +00:00
libgm2 Daily bump. 2023-12-14 00:18:00 +00:00
libgo libgo: update configure.ac to upstream GCC 2023-11-30 13:23:53 -08:00
libgomp Daily bump. 2023-12-19 00:17:36 +00:00
libgrust Daily bump. 2023-12-15 00:17:17 +00:00
libiberty Daily bump. 2023-12-06 00:17:50 +00:00
libitm Daily bump. 2023-10-23 00:16:43 +00:00
libobjc Daily bump. 2023-10-23 00:16:43 +00:00
libphobos Daily bump. 2023-12-19 00:17:36 +00:00
libquadmath Daily bump. 2023-12-13 00:17:49 +00:00
libsanitizer Daily bump. 2023-11-29 00:17:27 +00:00
libssp Daily bump. 2023-10-23 00:16:43 +00:00
libstdc++-v3 Daily bump. 2023-12-19 00:17:36 +00:00
libvtv Daily bump. 2023-10-23 00:16:43 +00:00
lto-plugin Daily bump. 2023-10-23 00:16:43 +00:00
maintainer-scripts Daily bump. 2023-11-14 12:23:39 +00:00
zlib Daily bump. 2023-10-23 00:16:43 +00:00
.dir-locals.el
.gitattributes
.gitignore *: add modern gettext 2023-11-14 00:47:11 +01:00
ABOUT-NLS
ar-lib
ChangeLog Daily bump. 2023-12-15 00:17:17 +00:00
ChangeLog.jit
ChangeLog.tree-ssa
compile
config-ml.in
config.guess
config.rpath
config.sub
configure build: Add libgrust as compilation modules 2023-12-14 13:58:57 +01:00
configure.ac build: Add libgrust as compilation modules 2023-12-14 13:58:57 +01:00
COPYING
COPYING.LIB
COPYING.RUNTIME
COPYING3
COPYING3.LIB
depcomp
install-sh
libtool-ldflags
libtool.m4 Build: fix error in fixinclude configure 2023-11-22 11:54:33 +01:00
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
lt~obsolete.m4
MAINTAINERS libgrust: Add entry for maintainers 2023-12-14 13:34:20 +01:00
Makefile.def build: Add libgrust as compilation modules 2023-12-14 13:58:57 +01:00
Makefile.in build: Add libgrust as compilation modules 2023-12-14 13:58:57 +01:00
Makefile.tpl Makefile.tpl: Avoid race condition in generating site.exp from the top level 2023-11-19 11:07:09 -05:00
missing
mkdep
mkinstalldirs
move-if-change
multilib.am
README
SECURITY.txt secpol: consistent indentation 2023-10-05 12:00:39 -04:00
symlink-tree
test-driver
ylwrap

This directory contains the GNU Compiler Collection (GCC).

The GNU Compiler Collection is free software.  See the files whose
names start with COPYING for copying permission.  The manuals, and
some of the runtime libraries, are under different terms; see the
individual source files for details.

The directory INSTALL contains copies of the installation information
as HTML and plain text.  The source of this information is
gcc/doc/install.texi.  The installation information includes details
of what is included in the GCC sources and what files GCC installs.

See the file gcc/doc/gcc.texi (together with other files that it
includes) for usage and porting information.  An online readable
version of the manual is in the files gcc/doc/gcc.info*.

See http://gcc.gnu.org/bugs/ for how to report bugs usefully.

Copyright years on GCC source files may be listed using range
notation, e.g., 1987-2012, indicating that every year in the range,
inclusive, is a copyrightable year that could otherwise be listed
individually.