GCC modified for the FreeChainXenon project
1d260ab0e3
This patch adds checks for attempting to change the active member of a union by methods other than a member access expression. To be able to properly distinguish `*(&u.a) = ` from `u.a = `, this patch redoes the solution for c++/59950 to avoid extranneous *&; it seems that the only case that needed the workaround was when copying empty classes. This patch also ensures that constructors for a union field mark that field as the active member before entering the call itself; this ensures that modifications of the field within the constructor's body don't cause false positives (as these will not appear to be member access expressions). This means that we no longer need to start the lifetime of empty union members after the constructor body completes. As a drive-by fix, this patch also ensures that value-initialised unions are considered to have activated their initial member for the purpose of checking stores and accesses, which catches some additional mistakes pre-C++20. PR c++/101631 PR c++/102286 gcc/cp/ChangeLog: * call.cc (build_over_call): Fold more indirect refs for trivial assignment op. * class.cc (type_has_non_deleted_trivial_default_ctor): Create. * constexpr.cc (cxx_eval_call_expression): Start lifetime of union member before entering constructor. (cxx_eval_component_reference): Check against first member of value-initialised union. (cxx_eval_store_expression): Activate member for value-initialised union. Check for accessing inactive union member indirectly. * cp-tree.h (type_has_non_deleted_trivial_default_ctor): Forward declare. gcc/testsuite/ChangeLog: * g++.dg/cpp1y/constexpr-89336-3.C: Fix union initialisation. * g++.dg/cpp1y/constexpr-union6.C: New test. * g++.dg/cpp1y/constexpr-union7.C: New test. * g++.dg/cpp2a/constexpr-union2.C: New test. * g++.dg/cpp2a/constexpr-union3.C: New test. * g++.dg/cpp2a/constexpr-union4.C: New test. * g++.dg/cpp2a/constexpr-union5.C: New test. * g++.dg/cpp2a/constexpr-union6.C: New test. Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com> Reviewed-by: Jason Merrill <jason@redhat.com> |
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| c++tools | ||
| config | ||
| contrib | ||
| fixincludes | ||
| gcc | ||
| gnattools | ||
| gotools | ||
| include | ||
| INSTALL | ||
| intl | ||
| libada | ||
| libatomic | ||
| libbacktrace | ||
| libcc1 | ||
| libcody | ||
| libcpp | ||
| libdecnumber | ||
| libffi | ||
| libgcc | ||
| libgfortran | ||
| libgm2 | ||
| libgo | ||
| libgomp | ||
| libiberty | ||
| libitm | ||
| libobjc | ||
| 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 | ||
| 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.