On Wed, Nov 22, 2017 at 3:06 AM, Jonathan Wakely <jwak...@redhat.com> wrote: > On 22/11/17 10:56 +0000, Jonathan Wakely wrote: >> >> On 22/11/17 11:23 +0100, Rainer Orth wrote: >>> >>> Hi Jonathan, >>> >>>> This uses static_assert to improve the errors when attempting to >>>> instantiate invalid specializations of containers, e.g. set<const T>, >>>> or unordered_set<int, equal_to<int>, hash<int>> (which mixes up the >>>> order of the hasher and equality predicate arguments). >>>> >>>> This means instead of more than 100 lines of confusing errors for >>>> https://wandbox.org/permlink/kL1YVNVOzrAsLPyS we get only this: >>>> >>>> In file included from /home/jwakely/gcc/8/include/c++/8.0.0/set:61:0, >>>> from s.cc:2: >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/stl_set.h: In instantiation >>>> of ‘class std::set<const int>’: >>>> s.cc:8:18: required from here >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/stl_set.h:108:7: error: >>>> static assertion failed: std::set must have a non-const, non-volatile >>>> value_type >>>> static_assert(is_same<typename remove_cv<_Key>::type, _Key>::value, >>>> ^~~~~~~~~~~~~ >>>> In file included from >>>> /home/jwakely/gcc/8/include/c++/8.0.0/unordered_set:46:0, >>>> from s.cc:1: >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/hashtable.h: In instantiation >>>> of ‘class std::_Hashtable<int, int, std::allocator<int>, >>>> std::__detail::_Identity, std::hash<int>, std::equal_to<int>, >>>> std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, >>>> std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, >>>> true, false> >’: >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/unordered_set.h:898:18: >>>> required from ‘class std::unordered_multiset<int, std::equal_to<int>, >>>> std::hash<int> >’ >>>> s.cc:10:53: required from here >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/hashtable.h:195:7: error: >>>> static assertion failed: hash function must be invocable with an argument >>>> of >>>> key type >>>> static_assert(__is_invocable<const _H1&, const _Key&>{}, >>>> ^~~~~~~~~~~~~ >>>> /home/jwakely/gcc/8/include/c++/8.0.0/bits/hashtable.h:197:7: error: >>>> static assertion failed: key equality predicate must be invocable with two >>>> arguments of key type >>>> static_assert(__is_invocable<const _Equal&, const _Key&, const >>>> _Key&>{}, >>>> ^~~~~~~~~~~~~ >>>> >>>> Tested powerpc64le-linux, committed to trunk. >>> >>> >>> this broke Go bootstrap, it seems. Seen on i386-pc-solaris2.11 as of >>> r255048: >>> >>> In file included from >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/map:60, >>> from /vol/gcc/src/hg/trunk/local/gcc/go/go-system.h:36, >>> from >>> /vol/gcc/src/hg/trunk/local/gcc/go/gofrontend/ast-dump.cc:7: >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_tree.h: >>> In instantiation of 'class std::_Rb_tree<Import_init*, Import_init*, >>> std::_Identity<Import_init*>, Import_init_lt, std::allocator<Import_init*> >>> >': >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_set.h:133:17: >>> required from 'class std::set<Import_init*, Import_init_lt>' >>> /vol/gcc/src/hg/trunk/local/gcc/go/gofrontend/gogo.h:127:37: required >>> from here >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_tree.h:452:7: >>> error: static assertion failed: comparison object must be invocable with two >>> arguments of key type >>> static_assert(__is_invocable<const _Compare&, const _Key&, const >>> _Key&>{}, >>> ^~~~~~~~~~~~~ >>> In file included from >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/map:60, >>> from /vol/gcc/src/hg/trunk/local/gcc/go/go-system.h:36, >>> from >>> /vol/gcc/src/hg/trunk/local/gcc/go/gofrontend/escape.cc:7: >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_tree.h: >>> In instantiation of 'class std::_Rb_tree<Import_init*, Import_init*, >>> std::_Identity<Import_init*>, Import_init_lt, std::allocator<Import_init*> >>> >': >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_set.h:133:17: >>> required from 'class std::set<Import_init*, Import_init_lt>' >>> /vol/gcc/src/hg/trunk/local/gcc/go/gofrontend/gogo.h:127:37: required >>> from here >>> >>> /var/gcc/regression/trunk/11.4-gcc/build/prev-i386-pc-solaris2.11/libstdc++-v3/include/bits/stl_tree.h:452:7: >>> error: static assertion failed: comparison object must be invocable with two >>> arguments of key type >>> static_assert(__is_invocable<const _Compare&, const _Key&, const >>> _Key&>{}, >>> ^~~~~~~~~~~~~ >> >> >> This is PR83102. I'm going to relax the checks, but the Go >> frontend still needs to be fixed. >> >> > > This should allow Go to build again (unless you bootstrap with > -std=gnu++17 in the build flags)
Thanks. Committed. Ian
