https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88115
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:61827d5d9a5a09a8c05d5e41f95b03ebc6c43f61 commit r11-4925-g61827d5d9a5a09a8c05d5e41f95b03ebc6c43f61 Author: Patrick Palka <ppa...@redhat.com> Date: Wed Nov 11 14:43:39 2020 -0500 c++: Correct the handling of alignof(expr) [PR88115] We're currently neglecting to set the ALIGNOF_EXPR_STD_P flag on an ALIGNOF_EXPR when its operand is an expression. This leads to us handling alignof(expr) as if it were written __alignof__(expr), and returning the preferred alignment instead of the ABI alignment. In the testcase below, this causes the first and third static_assert to fail on x86. gcc/cp/ChangeLog: PR c++/88115 * cp-tree.h (cxx_sizeof_or_alignof_expr): Add bool parameter. * decl.c (fold_sizeof_expr): Pass false to cxx_sizeof_or_alignof_expr. * parser.c (cp_parser_unary_expression): Pass std_alignof to cxx_sizeof_or_alignof_expr. * pt.c (tsubst_copy): Pass false to cxx_sizeof_or_alignof_expr. (tsubst_copy_and_build): Pass std_alignof to cxx_sizeof_or_alignof_expr. * typeck.c (cxx_alignof_expr): Add std_alignof bool parameter and pass it to cxx_sizeof_or_alignof_type. Set ALIGNOF_EXPR_STD_P appropriately. (cxx_sizeof_or_alignof_expr): Add std_alignof bool parameter and pass it to cxx_alignof_expr. Assert op is either SIZEOF_EXPR or ALIGNOF_EXPR. libcc1/ChangeLog: PR c++/88115 * libcp1plugin.cc (plugin_build_unary_expr): Pass true to cxx_sizeof_or_alignof_expr. gcc/testsuite/ChangeLog: PR c++/88115 * g++.dg/cpp0x/alignof6.C: New test.
