![]() Since -Wdangling-reference has false positives that can't be prevented, we should offer an easy way to suppress the warning. Currently, that is only possible by using a #pragma, either around the enclosing class or around the call site. But #pragma GCC diagnostic tend to be onerous. A better solution would be to have an attribute. To that end, this patch adds a new attribute, [[gnu::no_dangling]]. This attribute takes an optional bool argument to support cases like: template <typename T> struct [[gnu::no_dangling(std::is_reference_v<T>)]] S { // ... }; PR c++/110358 PR c++/109642 gcc/cp/ChangeLog: * call.cc (no_dangling_p): New. (reference_like_class_p): Use it. (do_warn_dangling_reference): Use it. Don't warn when the function or its enclosing class has attribute gnu::no_dangling. * tree.cc (cxx_gnu_attributes): Add gnu::no_dangling. (handle_no_dangling_attribute): New. gcc/ChangeLog: * doc/extend.texi: Document gnu::no_dangling. * doc/invoke.texi: Mention that gnu::no_dangling disables -Wdangling-reference. gcc/testsuite/ChangeLog: * g++.dg/ext/attr-no-dangling1.C: New test. * g++.dg/ext/attr-no-dangling2.C: New test. * g++.dg/ext/attr-no-dangling3.C: New test. * g++.dg/ext/attr-no-dangling4.C: New test. * g++.dg/ext/attr-no-dangling5.C: New test. * g++.dg/ext/attr-no-dangling6.C: New test. * g++.dg/ext/attr-no-dangling7.C: New test. * g++.dg/ext/attr-no-dangling8.C: New test. * g++.dg/ext/attr-no-dangling9.C: New test. |
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c++tools | ||
config | ||
contrib | ||
fixincludes | ||
gcc | ||
gnattools | ||
gotools | ||
include | ||
INSTALL | ||
libada | ||
libatomic | ||
libbacktrace | ||
libcc1 | ||
libcody | ||
libcpp | ||
libdecnumber | ||
libffi | ||
libgcc | ||
libgfortran | ||
libgm2 | ||
libgo | ||
libgomp | ||
libgrust | ||
libiberty | ||
libitm | ||
libobjc | ||
libphobos | ||
libquadmath | ||
libsanitizer | ||
libssp | ||
libstdc++-v3 | ||
libvtv | ||
lto-plugin | ||
maintainer-scripts | ||
zlib | ||
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.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 | ||
COPYING.LIB | ||
COPYING.RUNTIME | ||
COPYING3 | ||
COPYING3.LIB | ||
depcomp | ||
install-sh | ||
libtool-ldflags | ||
libtool.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
lt~obsolete.m4 | ||
MAINTAINERS | ||
Makefile.def | ||
Makefile.in | ||
Makefile.tpl | ||
missing | ||
mkdep | ||
mkinstalldirs | ||
move-if-change | ||
multilib.am | ||
README | ||
SECURITY.txt | ||
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.