https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85723
Bug ID: 85723
Summary: [C++17][DR 1496] __is_trivial intrinsic fails with no
trivial non-deleted default c'tor
Product: gcc
Version: 8.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: joseph_marino at hotmail dot com
Target Milestone: ---
gcc version 8.1.0 (GCC-Explorer-Build) when compiled with the flags:
-std=c++17 -Wall -Wextra
rejects the following code:
struct NonTrivial { NonTrivial() = delete; };
static_assert(!__is_trivial (NonTrivial), "NonTrivial is trivial");
emitting:
<source>:2:15: error: static assertion failed: NonTrivial is trivial
The assert should pass, as all default constructors of NonTrivial are deleted,
which does not meet the requirements in 12 [class] p6:
A trivial class is a class that is trivially copyable and has one or more
default constructors (15.1), all of which are either trivial or deleted and
**at least one of which is not deleted**.
This wording was introduced by the acceptance of DR 1496.
Full contents of compiling with -v follow:
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-8.1.0/bin/g++
Target: x86_64-linux-gnu
Configured with: ../gcc-8.1.0/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu --enable-languages=c,c++,fortran
--enable-ld=yes --enable-gold=yes --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --enable-linker-build-id --enable-lto
--enable-plugins --enable-threads=posix --with-pkgversion=GCC-Explorer-Build
Thread model: posix
gcc version 8.1.0 (GCC-Explorer-Build)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o'
'/tmp/compiler-explorer-compiler11849-52-1aa40zw.lzvg/output.s' '-masm=intel'
'-S' '-v' '-std=c++17' '-Wall' '-Wextra' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
/opt/compiler-explorer/gcc-8.1.0/bin/../libexec/gcc/x86_64-linux-gnu/8.1.0/cc1plus
-quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/
-D_GNU_SOURCE <source> -quiet -dumpbase example.cpp -masm=intel -mtune=generic
-march=x86-64 -auxbase-strip
/tmp/compiler-explorer-compiler11849-52-1aa40zw.lzvg/output.s -g -Wall -Wextra
-std=c++17 -version -fdiagnostics-color=always -o
/tmp/compiler-explorer-compiler11849-52-1aa40zw.lzvg/output.s
GNU C++17 (GCC-Explorer-Build) version 8.1.0 (x86_64-linux-gnu)
compiled by GNU C version 5.4.0 20160609, GMP version 6.1.0, MPFR
version 3.1.4, MPC version 1.0.3, isl version isl-0.18-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0/backward"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/include"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/include-fixed"
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory "/usr/include/x86_64-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
/usr/include/x86_64-linux-gnu
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0/x86_64-linux-gnu
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/../../../../include/c++/8.1.0/backward
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/include
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/x86_64-linux-gnu/8.1.0/include-fixed
/usr/local/include
/opt/compiler-explorer/gcc-8.1.0/bin/../lib/gcc/../../include
/usr/include
End of search list.
GNU C++17 (GCC-Explorer-Build) version 8.1.0 (x86_64-linux-gnu)
compiled by GNU C version 5.4.0 20160609, GMP version 6.1.0, MPFR
version 3.1.4, MPC version 1.0.3, isl version isl-0.18-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 2a4ed8141a9e6ff21b9c06e24d4e4c1a
<source>:2:15: error: static assertion failed: NonTrivial is trivial
static_assert(!__is_trivial (NonTrivial), "NonTrivial is trivial");
^~~~~~~~~~~~~~~~~~~~~~~~~~
Compiler returned: 1
