43ab1dc24a
Tim Song pointed out that using __underlying_type is ill-formed for incomplete enumeration types, and is_scoped_enum doesn't require a complete type. This changes the trait to check for conversion to int instead of to the underlying type. In order to give the correct result when the trait is used in the enumerator-list of an incomplete type the partial specialization for enums has an additional check that fails for incomplete types. This assumes that an incompelte enumeration type must be an unscoped enumeration, and so the primary template (with a std::false_type base characteristic) can be used. This isn't necessarily true, but it is not currently possible to refer to a scoped enumeration type before its type is complete (PR c++/89025). It should be possible to use requires(remove_cv_t<_Tp> __t) in the partial specialization's assignablility check, but that currently gives an ICE (PR c++/99968) so there is an extra partial specialization of is_scoped_enum<const _Tp> to handle const types. libstdc++-v3/ChangeLog: * include/std/type_traits (is_scoped_enum<T>): Constrain partial specialization to not match incomplete enum types. Use a requires-expression instead of instantiating is_convertible. (is_scoped_enum<const T>): Add as workaround for PR c++/99968. * testsuite/20_util/is_scoped_enum/value.cc: Check with incomplete types and opaque-enum-declarations. |
||
---|---|---|
c++tools | ||
config | ||
contrib | ||
fixincludes | ||
gcc | ||
gnattools | ||
gotools | ||
include | ||
INSTALL | ||
intl | ||
libada | ||
libatomic | ||
libbacktrace | ||
libcc1 | ||
libcody | ||
libcpp | ||
libdecnumber | ||
libffi | ||
libgcc | ||
libgfortran | ||
libgo | ||
libgomp | ||
libhsail-rt | ||
libiberty | ||
libitm | ||
libobjc | ||
liboffloadmic | ||
libphobos | ||
libquadmath | ||
libsanitizer | ||
libssp | ||
libstdc++-v3 | ||
libvtv | ||
lto-plugin | ||
maintainer-scripts | ||
zlib | ||
.dir-locals.el | ||
.gitattributes | ||
.gitignore | ||
ABOUT-NLS | ||
ar-lib | ||
ChangeLog | ||
ChangeLog.jit | ||
ChangeLog.tree-ssa | ||
compile | ||
config-ml.in | ||
config.guess | ||
config.rpath | ||
config.sub | ||
configure | ||
configure.ac | ||
COPYING | ||
COPYING3 | ||
COPYING3.LIB | ||
COPYING.LIB | ||
COPYING.RUNTIME | ||
depcomp | ||
install-sh | ||
libtool-ldflags | ||
libtool.m4 | ||
lt~obsolete.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
MAINTAINERS | ||
Makefile.def | ||
Makefile.in | ||
Makefile.tpl | ||
missing | ||
mkdep | ||
mkinstalldirs | ||
move-if-change | ||
multilib.am | ||
README | ||
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.