https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98367
Bug ID: 98367
Summary: ICE with CTAD non-type template parameter
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jbassett271 at gmail dot com
Target Milestone: ---
This ICEs the compiler with a segfault (see https://godbolt.org/z/ddceoM ):
template <typename A>
struct ctad_t {
A a;
};
template <ctad_t T>
struct myclass {
};
template <typename Something>
constexpr auto myobject = ctad_t {Something::value};
template <typename Something>
using thing = myclass<myobject<Something>>;
Compiled with (grabbed from the Compiler Explorer link): g++ -g -o output.s
-masm=intel -S -fdiagnostics-color=always -std=c++2a example.cpp
I have also confirmed this on my own machine with gcc version 10.1.0.
Tested with GCC versions on Compiler Explorer:
- gcc version 11.0.0 20201216 (experimental)
- gcc version 10.2.0
- gcc version 10.1.0
- gcc version 9.3.0
- gcc version 9.2.0
- gcc version 9.1.0
- gcc version 8.3.0
- gcc version 8.2.0
- gcc version 8.1.0
These also segfaulted with -std=c++1z instead of -std=c++2a:
- gcc version 7.5.0
- gcc version 7.4.0
- gcc version 7.3.0
- gcc version 7.2.0
- gcc version 7.1.0
Earlier versions did not support CTAD.
Inlining the `object` variable does not segfault, but emits a message about
being unable to perform CTAD: https://godbolt.org/z/drWT6h
