https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86875
Bug ID: 86875
Summary: internal compiler error: in tsubst_copy, at
cp/pt.c:15478
Product: gcc
Version: 8.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ldalessandro at gmail dot com
Target Milestone: ---
ICE in 8.2 (Debian gcc package) when capturing `const` variable in y_combinator
recursive lambda. This code works fine in 7.x. Capturing by reference or copy
makes no difference. Removing `const` suppresses the ICE.
Attached reduced test.ii test case.
* g++ -std=c++14 -c -o test.o test.ii
* Linux ****** 4.16.0-2-amd64 #1 SMP Debian 4.16.16-2 (2018-06-22) x86_64
GNU/Linux
* gcc version 8.2.0 (Debian 8.2.0-1)
* Configured with: ../src/configure -v --with-pkgversion='Debian 8.2.0-1'
--with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --program-suffix=-8
--program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie
--with-system-zlib --with-target-system-zlib --enable-objc-gc=auto
--enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-offload-targets=nvptx-none --without-cuda-driver
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
---------------------------------
# Terminal session with details #
---------------------------------
$ uname -a
Linux ****** 4.16.0-2-amd64 #1 SMP Debian 4.16.16-2 (2018-06-22) x86_64
GNU/Linux
$ gcc --version
gcc (Debian 8.2.0-1) 8.2.0
Copyright (C) 2018 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
$ cat test.cpp
#include <functional>
// Adapted from
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0200r0.html.
template<class Fun>
class y_combinator_result {
Fun fun_;
public:
template<class T>
explicit y_combinator_result(T &&fun): fun_(std::forward<T>(fun)) {}
template<class ...Args>
decltype(auto) operator()(Args &&...args) {
return fun_(std::ref(*this), std::forward<Args>(args)...);
}
};
template<class Fun>
decltype(auto) y_combinator(Fun &&fun) {
return y_combinator_result<std::decay_t<Fun>>(std::forward<Fun>(fun));
}
int main() {
const unsigned w = 1; // non-const works fine
auto foo = y_combinator([=](auto foo) -> void {
auto i = 0 + w;
foo();
});
foo();
return 0;
}
$ g++ -v -std=c++14 -save-temps -c -o test.o test.cpp
Using built-in specs.
COLLECT_GCC=g++
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 8.2.0-1'
--with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --program-suffix=-8
--program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie
--with-system-zlib --with-target-system-zlib --enable-objc-gc=auto
--enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-offload-targets=nvptx-none --without-cuda-driver
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 8.2.0 (Debian 8.2.0-1)
COLLECT_GCC_OPTIONS='-v' '-std=c++14' '-save-temps' '-c' '-o' 'test.o'
'-shared-libgcc' '-mtune=generic' '-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/8/cc1plus -E -quiet -v -imultiarch
x86_64-linux-gnu -D_GNU_SOURCE test.cpp -mtune=generic -march=x86-64 -std=c++14
-fpch-preprocess -o test.ii
ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/8"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/local/include"
ignoring nonexistent directory
"/usr/lib/gcc/x86_64-linux-gnu/8/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/opt/intel/compilers_and_libraries_2018.1.163/linux/mkl/include
/usr/include/c++/8
/usr/include/x86_64-linux-gnu/c++/8
/usr/include/c++/8/backward
/usr/lib/gcc/x86_64-linux-gnu/8/include
/usr/lib/gcc/x86_64-linux-gnu/8/include-fixed
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-std=c++14' '-save-temps' '-c' '-o' 'test.o'
'-shared-libgcc' '-mtune=generic' '-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/8/cc1plus -fpreprocessed test.ii -quiet
-dumpbase test.cpp -mtune=generic -march=x86-64 -auxbase-strip test.o
-std=c++14 -version -o test.s
GNU C++14 (Debian 8.2.0-1) version 8.2.0 (x86_64-linux-gnu)
compiled by GNU C version 8.2.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.19-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU C++14 (Debian 8.2.0-1) version 8.2.0 (x86_64-linux-gnu)
compiled by GNU C version 8.2.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.19-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 8ef452a0a06f9d64060be385354ae1d5
test.cpp: In instantiation of ‘main()::<lambda(auto:1)> [with auto:1 =
std::reference_wrapper<y_combinator_result<main()::<lambda(auto:1)> > >]’:
test.cpp:13:61: required from ‘decltype(auto)
y_combinator_result<Fun>::operator()(Args&& ...) [with Args = {}; Fun =
main()::<lambda(auto:1)>]’
test.cpp:28:7: required from here
test.cpp:25:18: internal compiler error: in tsubst_copy, at cp/pt.c:15478
auto i = 0 + w;
~~^~~
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-8/README.Bugs> for instructions.
make: *** [<builtin>: test.o] Error 1
$ apt show gcc
Package: gcc
Version: 4:8.1.0-1
Priority: optional
Build-Essential: yes
Section: devel
Source: gcc-defaults (1.178)
Maintainer: Debian GCC Maintainers <debian-...@lists.debian.org>
Installed-Size: 46.1 kB
Provides: c-compiler, gcc-x86-64-linux-gnu (= 4:8.1.0-1)
Depends: cpp (= 4:8.1.0-1), gcc-8 (>= 8.1.0-4~)
Recommends: libc6-dev | libc-dev
Suggests: gcc-multilib, make, manpages-dev, autoconf, automake, libtool, flex,
bison, gdb, gcc-doc
Conflicts: gcc-doc (<< 1:2.95.3)
Tag: devel::compiler, devel::lang:c, devel::library, implemented-in::c,
interface::commandline, role::devel-lib, role::metapackage,
role::program, suite::gnu, works-with::software:source
Download-Size: 5,192 B
APT-Manual-Installed: yes
APT-Sources: http://mirrors.cat.pdx.edu/debian testing/main amd64 Packages
Description: GNU C compiler
This is the GNU C compiler, a fairly portable optimizing compiler for C.
.
This is a dependency package providing the default GNU C compiler.
