https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115806
--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Simon Martin <simar...@gcc.gnu.org>: https://gcc.gnu.org/g:786ebbd6058540b2110da16a693f0c582c11413c commit r15-2855-g786ebbd6058540b2110da16a693f0c582c11413c Author: Simon Martin <si...@nasilyan.com> Date: Thu Aug 8 14:59:49 2024 +0200 c++: Don't accept multiple enum definitions within template class [PR115806] We have been accepting the following invalid code since revision 557831a91df === cut here === template <typename T> struct S { enum E { a }; enum E { b }; }; S<int> s; === cut here === The problem is that start_enum will set OPAQUE_ENUM_P to true even if it retrieves an existing definition for the enum, which causes the redefinition check in cp_parser_enum_specifier to be bypassed. This patch only sets OPAQUE_ENUM_P and ENUM_FIXED_UNDERLYING_TYPE_P when actually pushing a new tag for the enum. PR c++/115806 gcc/cp/ChangeLog: * decl.cc (start_enum): Only set OPAQUE_ENUM_P and ENUM_FIXED_UNDERLYING_TYPE_P when pushing a new tag. gcc/testsuite/ChangeLog: * g++.dg/parse/enum15.C: New test.
