gcc/libiberty
Jason Merrill c3f281a0c1 c++: mangle function template constraints
Per https://github.com/itanium-cxx-abi/cxx-abi/issues/24 and
https://github.com/itanium-cxx-abi/cxx-abi/pull/166

We need to mangle constraints to be able to distinguish between function
templates that only differ in constraints.  From the latter link, we want to
use the template parameter mangling previously specified for lambdas to also
make explicit the form of a template parameter where the argument is not a
"natural" fit for it, such as when the parameter is constrained or deduced.

I'm concerned about how the latter link changes the mangling for some C++98
and C++11 patterns, so I've limited template_parm_natural_p to avoid two
cases found by running the testsuite with -Wabi forced on:

template <class T, T V> T f() { return V; }
int main() { return f<int,42>(); }

template <int i> int max() { return i; }
template <int i, int j, int... rest> int max()
{
  int sub = max<j, rest...>();
  return i > sub ? i : sub;
}
int main() {  return max<1,2,3>(); }

A third C++11 pattern is changed by this patch:

template <template <typename...> class TT, typename... Ts> TT<Ts...> f();
template <typename> struct A { };
int main() { f<A,int>(); }

I aim to resolve these with the ABI committee before GCC 14.1.

We also need to resolve https://github.com/itanium-cxx-abi/cxx-abi/issues/38
(mangling references to dependent template-ids where the name is fully
resolved) as references to concepts in std:: will consistently run into this
area.  This is why mangle-concepts1.C only refers to concepts in the global
namespace so far.

The library changes are to avoid trying to mangle builtins, which fails.

Demangler support and test coverage is not complete yet.

gcc/cp/ChangeLog:

	* cp-tree.h (TEMPLATE_ARGS_TYPE_CONSTRAINT_P): New.
	(get_concept_check_template): Declare.
	* constraint.cc (combine_constraint_expressions)
	(finish_shorthand_constraint): Use UNKNOWN_LOCATION.
	* pt.cc (convert_generic_types_to_packs): Likewise.
	* mangle.cc (write_constraint_expression)
	(write_tparms_constraints, write_type_constraint)
	(template_parm_natural_p, write_requirement)
	(write_requires_expr): New.
	(write_encoding): Mangle trailing requires-clause.
	(write_name): Pass parms to write_template_args.
	(write_template_param_decl): Factor out from...
	(write_closure_template_head): ...here.
	(write_template_args): Mangle non-natural parms
	and requires-clause.
	(write_expression): Handle REQUIRES_EXPR.

include/ChangeLog:

	* demangle.h (enum demangle_component_type): Add
	DEMANGLE_COMPONENT_CONSTRAINTS.

libiberty/ChangeLog:

	* cp-demangle.c (d_make_comp): Handle
	DEMANGLE_COMPONENT_CONSTRAINTS.
	(d_count_templates_scopes): Likewise.
	(d_print_comp_inner): Likewise.
	(d_maybe_constraints): New.
	(d_encoding, d_template_args_1): Call it.
	(d_parmlist): Handle 'Q'.
	* testsuite/demangle-expected: Add some constraint tests.

libstdc++-v3/ChangeLog:

	* include/std/bit: Avoid builtins in requires-clauses.
	* include/std/variant: Likewise.

gcc/testsuite/ChangeLog:

	* g++.dg/abi/mangle10.C: Disable compat aliases.
	* g++.dg/abi/mangle52.C: Specify ABI 18.
	* g++.dg/cpp2a/class-deduction-alias3.C
	* g++.dg/cpp2a/class-deduction-alias8.C:
	Avoid builtins in requires-clauses.
	* g++.dg/abi/mangle-concepts1.C: New test.
	* g++.dg/abi/mangle-ttp1.C: New test.
2023-12-01 16:08:25 -05:00
..
config
testsuite c++: mangle function template constraints 2023-12-01 16:08:25 -05:00
_doprnt.c Update copyright years. 2023-01-16 11:52:17 +01:00
.gitignore
acinclude.m4 Update copyright years. 2023-01-16 11:52:17 +01:00
aclocal.m4 libiberty: Disable hwcaps for sha1.o 2023-11-30 10:06:23 +01:00
alloca.c
argv.c libiberty: writeargv: Simplify function error mode. 2023-06-06 20:50:07 -06:00
asprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
at-file.texi Revert "sphinx: remove texinfo files" 2022-11-14 09:35:06 +01:00
atexit.c
basename.c
bcmp.c
bcopy.c
bsearch_r.c
bsearch.c
bzero.c
calloc.c
ChangeLog Daily bump. 2023-12-01 00:17:36 +00:00
ChangeLog.jit
choose-temp.c Update copyright years. 2023-01-16 11:52:17 +01:00
clock.c Update copyright years. 2023-01-16 11:52:17 +01:00
concat.c Update copyright years. 2023-01-16 11:52:17 +01:00
config.h-vms
config.in libiberty: Use x86 HW optimized sha1 2023-11-28 13:14:05 +01:00
configure libiberty: Disable hwcaps for sha1.o 2023-11-30 10:06:23 +01:00
configure.ac libiberty: Disable hwcaps for sha1.o 2023-11-30 10:06:23 +01:00
configure.com
copying-lib.texi Update copyright years. 2023-01-16 11:52:17 +01:00
COPYING.LIB
copysign.c
cp-demangle.c c++: mangle function template constraints 2023-12-01 16:08:25 -05:00
cp-demangle.h Update copyright years. 2023-01-16 11:52:17 +01:00
cp-demint.c Update copyright years. 2023-01-16 11:52:17 +01:00
cplus-dem.c Update copyright years. 2023-01-16 11:52:17 +01:00
crc32.c Update copyright years. 2023-01-16 11:52:17 +01:00
d-demangle.c Update copyright years. 2023-01-16 11:52:17 +01:00
dwarfnames.c Update copyright years. 2023-01-16 11:52:17 +01:00
dyn-string.c Update copyright years. 2023-01-16 11:52:17 +01:00
fdmatch.c Update copyright years. 2023-01-16 11:52:17 +01:00
ffs.c
fibheap.c Update copyright years. 2023-01-16 11:52:17 +01:00
filedescriptor.c Update copyright years. 2023-01-16 11:52:17 +01:00
filename_cmp.c Update copyright years. 2023-01-16 11:52:17 +01:00
floatformat.c Update copyright years. 2023-01-16 11:52:17 +01:00
fnmatch.c Update copyright years. 2023-01-16 11:52:17 +01:00
fnmatch.txh
fopen_unlocked.c Update copyright years. 2023-01-16 11:52:17 +01:00
functions.texi Revert "sphinx: remove texinfo files" 2022-11-14 09:35:06 +01:00
gather-docs Update copyright years. 2023-01-16 11:52:17 +01:00
getcwd.c
getopt1.c Update copyright years. 2023-01-16 11:52:17 +01:00
getopt.c Update copyright years. 2023-01-16 11:52:17 +01:00
getpagesize.c
getpwd.c
getruntime.c Update copyright years. 2023-01-16 11:52:17 +01:00
gettimeofday.c
hashtab.c Update copyright years. 2023-01-16 11:52:17 +01:00
hex.c Update copyright years. 2023-01-16 11:52:17 +01:00
index.c
insque.c
lbasename.c Update copyright years. 2023-01-16 11:52:17 +01:00
libiberty.texi Update copyright years. 2023-01-16 11:52:17 +01:00
lrealpath.c libiberty: fix lrealpath on Windows NTFS symlinks 2023-02-11 06:29:43 +00:00
maint-tool Update copyright years. 2023-01-16 11:52:17 +01:00
make-relative-prefix.c Update copyright years. 2023-01-16 11:52:17 +01:00
make-temp-file.c Update copyright years. 2023-01-16 11:52:17 +01:00
Makefile.in libiberty: Disable hwcaps for sha1.o 2023-11-30 10:06:23 +01:00
makefile.vms
md5.c Update copyright years. 2023-01-16 11:52:17 +01:00
memchr.c
memcmp.c
memcpy.c
memmem.c Update copyright years. 2023-01-16 11:52:17 +01:00
memmove.c
mempcpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
memset.c
mkstemps.c Update copyright years. 2023-01-16 11:52:17 +01:00
msdos.c
objalloc.c Update copyright years. 2023-01-16 11:52:17 +01:00
obstack.c Update copyright years. 2023-01-16 11:52:17 +01:00
obstacks.texi libiberty: Remove a reference to the Glibc manual 2023-03-30 23:41:24 +02:00
partition.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-common.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-common.h Update copyright years. 2023-01-16 11:52:17 +01:00
pex-djgpp.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-msdos.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-one.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-unix.c [PATCH v3] libiberty: Use posix_spawn in pex-unix when available. 2023-11-09 21:01:58 -07:00
pex-win32.c libiberty: pex-win32.c: Fix some typos. 2023-06-05 12:13:28 +00:00
pexecute.c Update copyright years. 2023-01-16 11:52:17 +01:00
pexecute.txh
physmem.c Update copyright years. 2023-01-16 11:52:17 +01:00
putenv.c Update copyright years. 2023-01-16 11:52:17 +01:00
random.c
README
regex.c Update copyright years. 2023-01-16 11:52:17 +01:00
rename.c
rindex.c
rust-demangle.c Update copyright years. 2023-01-16 11:52:17 +01:00
safe-ctype.c Update copyright years. 2023-01-16 11:52:17 +01:00
setenv.c Update copyright years. 2023-01-16 11:52:17 +01:00
setproctitle.c Update copyright years. 2023-01-16 11:52:17 +01:00
sha1.c libiberty: Use x86 HW optimized sha1 2023-11-28 13:14:05 +01:00
sigsetmask.c
simple-object-coff.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-common.h Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-elf.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-mach-o.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-xcoff.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object.txh
snprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
sort.c Update copyright years. 2023-01-16 11:52:17 +01:00
spaces.c Update copyright years. 2023-01-16 11:52:17 +01:00
splay-tree.c Update copyright years. 2023-01-16 11:52:17 +01:00
stack-limit.c Update copyright years. 2023-01-16 11:52:17 +01:00
stpcpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
stpncpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
strcasecmp.c
strchr.c
strdup.c
strerror.c
strncasecmp.c
strncmp.c
strndup.c Update copyright years. 2023-01-16 11:52:17 +01:00
strnlen.c
strrchr.c
strsignal.c
strstr.c libiberty: Make strstr.c in libiberty ANSI compliant 2023-04-02 20:05:31 +02:00
strtod.c Update copyright years. 2023-01-16 11:52:17 +01:00
strtol.c
strtoll.c
strtoul.c
strtoull.c
strverscmp.c Update copyright years. 2023-01-16 11:52:17 +01:00
timeval-utils.c Update copyright years. 2023-01-16 11:52:17 +01:00
tmpnam.c
unlink-if-ordinary.c Update copyright years. 2023-01-16 11:52:17 +01:00
vasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vfork.c
vfprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf-support.c Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf-support.h Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf.c
vsnprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vsprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
waitpid.c
xasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
xatexit.c
xexit.c Update copyright years. 2023-01-16 11:52:17 +01:00
xmalloc.c Update copyright years. 2023-01-16 11:52:17 +01:00
xmemdup.c
xstrdup.c
xstrerror.c
xstrndup.c Update copyright years. 2023-01-16 11:52:17 +01:00
xvasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00

This directory contains the -liberty library of free software.
It is a collection of subroutines used by various GNU programs.
Current members include:

	getopt -- get options from command line
	obstack -- stacks of arbitrarily-sized objects
	strerror -- error message strings corresponding to errno
	strtol -- string-to-long conversion
	strtoul -- string-to-unsigned-long conversion

We expect many of the GNU subroutines that are floating around to
eventually arrive here.

The library must be configured from the top source directory.  Don't
try to run configure in this directory.  Follow the configuration
instructions in ../README.

Please report bugs to https://gcc.gnu.org/bugzilla/ and send fixes to
"gcc-patches@gcc.gnu.org".  Thank you.

ADDING A NEW FILE
=================

There are two sets of files:  Those that are "required" will be
included in the library for all configurations, while those
that are "optional" will be included in the library only if "needed."

To add a new required file, edit Makefile.in to add the source file
name to CFILES and the object file to REQUIRED_OFILES.

To add a new optional file, it must provide a single function, and the
name of the function must be the same as the name of the file.

    * Add the source file name to CFILES in Makefile.in and the object
      file to CONFIGURED_OFILES.

    * Add the function to name to the funcs shell variable in
      configure.ac.

    * Add the function to the AC_CHECK_FUNCS lists just after the
      setting of the funcs shell variable.  These AC_CHECK_FUNCS calls
      are never executed; they are there to make autoheader work
      better.

    * Consider the special cases of building libiberty; as of this
      writing, the special cases are newlib and VxWorks.  If a
      particular special case provides the function, you do not need
      to do anything.  If it does not provide the function, add the
      object file to LIBOBJS, and add the function name to the case
      controlling whether to define HAVE_func.

Finally, in the build directory of libiberty, configure with
"--enable-maintainer-mode", run "make maint-deps" to update
Makefile.in, and run 'make stamp-functions' to regenerate
functions.texi.

The optional file you've added (e.g. getcwd.c) should compile and work
on all hosts where it is needed.  It does not have to work or even
compile on hosts where it is not needed.

ADDING A NEW CONFIGURATION
==========================

On most hosts you should be able to use the scheme for automatically
figuring out which files are needed.  In that case, you probably
don't need a special Makefile stub for that configuration.

If the fully automatic scheme doesn't work, you may be able to get
by with defining EXTRA_OFILES in your Makefile stub.  This is
a list of object file names that should be treated as required
for this configuration - they will be included in libiberty.a,
regardless of whatever might be in the C library.