https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113584
Bug ID: 113584
Summary: ICE in unify, at cp/pt.cc:24640 with template
specialization on 2 matching template template
parameter
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jonathan.poelen at gmail dot com
Target Milestone: ---
A link that reproduces the problem on godbolt (with trunk which is currently
gcc 14.0): https://godbolt.org/z/Yn7dEG96e
The code compiles with clang. It also compiles if one of the 2 specializations
is deleted.
The output of -freport-bug with a gcc 13.2 (what I have on my computer).
// Target: x86_64-pc-linux-gnu
// Configured with: /build/gcc/src/gcc/configure
--enable-languages=ada,c,c++,d,fortran,go,lto,objc,obj-c++ --enable-bootstrap
--prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man
--infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/
--with-build-config=bootstrap-lto --with-linker-hash-style=gnu
--with-system-zlib --enable-__cxa_atexit --enable-cet=auto
--enable-checking=release --enable-clocale=gnu --enable-default-pie
--enable-default-ssp --enable-gnu-indirect-function --enable-gnu-unique-object
--enable-libstdcxx-backtrace --enable-link-serialization=1
--enable-linker-build-id --enable-lto --enable-multilib --enable-plugin
--enable-shared --enable-threads=posix --disable-libssp --disable-libstdcxx-pch
--disable-werror
// Thread model: posix
// Supported LTO compression algorithms: zlib zstd
// gcc version 13.2.1 20230801 (GCC)
//
// test2.cpp:25:38: internal compiler error: in unify, at cp/pt.cc:24606
// 25 | using R = normalize_similar2<px<int>>::type;
// | ^~
// 0x1ad33c8 internal_error(char const*, ...)
// ???:0
// 0x6b7b63 fancy_abort(char const*, int, char const*)
// ???:0
// 0x8729fd most_specialized_partial_spec(tree_node*, int)
// ???:0
// 0x875849 instantiate_class_template(tree_node*)
// ???:0
// 0x8be335 complete_type(tree_node*)
// ???:0
// 0x9443d0 c_common_parse_file()
// ???:0
// Please submit a full bug report, with preprocessed source.
// Please include the complete backtrace with any bug report.
// See <https://bugs.archlinux.org/> for instructions.
// /usr/lib/gcc/x86_64-pc-linux-gnu/13.2.1/cc1plus -quiet -D_GNU_SOURCE
test2.cpp -quiet -dumpdir a- -dumpbase test2.cpp -dumpbase-ext .cpp
-mtune=generic -march=x86-64 -fsyntax-only -freport-bug -o - -frandom-seed=0
-fdump-noaddr
# 0 "test2.cpp"
# 0 "<built-in>"
# 0 "<command-line>"
# 1 "/usr/include/stdc-predef.h" 1 3 4
# 0 "<command-line>" 2
# 1 "test2.cpp"
template<template<class T, T...> class Tpl>
struct tpl_type2;
template<template<class, unsigned...> class Tpl>
struct tpl_type3;
template<class T>
struct normalize_similar2
{};
template<class T, template<class, T...> class Tpl, T... xs>
struct normalize_similar2<Tpl<T, xs...>>
{
using type = tpl_type2<Tpl>;
};
template<template<class, unsigned...> class Tpl, class T, unsigned... N>
struct normalize_similar2<Tpl<T, N...>>
{
using type = tpl_type3<Tpl>;
};
template<class T, T...> struct px;
using R = normalize_similar2<px<int>>::type;
