https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112633
Bug ID: 112633
Summary: ICE in parser GCC 13+ (including 14) around type
aliases
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: hanicka at hanicka dot net
Target Milestone: ---
Tested on GCC 14.0.0 20231119 (on Compiler-Explorer) and it's giving me ICE,
also on all 13.x versions (not 12.x)
```c++
template <class> constexpr bool dependent_true = true;
template <bool> struct empty_type { }; // something like enable_if
template <bool B> using empty_type_t = typename empty_type<B>::type;
struct wrapper {
using type = void;
};
template <class...> using all = wrapper;
template <class... Conditions>
using constraints = typename all<Conditions...>::type;
template <typename T, constraints<empty_type_t<dependent_true<T>>> = nullptr>
void calculate() { };
```
I don't even need to instantiate `calculate` function.
It gives me this error:
<source>: In substitution of 'template<class ... Conditions> using constraints
= typename all<Conditions ...>::type [with Conditions = {typename
empty_type<dependent_true<T> >::type}]':
<source>:16:66: required from here
16 | template <typename T, constraints<empty_type_t<dependent_true<T>>> =
nullptr>
| ^
<source>:14:7: internal compiler error: Segmentation fault
14 | using constraints = typename all<Conditions...>::type;
| ^~~~~~~~~~~
0x26a742e internal_error(char const*, ...)
???:0
0xd276f0 tsubst(tree_node*, tree_node*, int, tree_node*)
???:0
0xd1b8f3 instantiate_template(tree_node*, tree_node*, int)
???:0
0xd285ea tsubst(tree_node*, tree_node*, int, tree_node*)
???:0
0xd35ed6 lookup_template_class(tree_node*, tree_node*, tree_node*, tree_node*,
int, int)
???:0
0xd6996f finish_template_type(tree_node*, tree_node*, int)
???:0
0xcf6a49 c_parse_file()
???:0
0xe38e79 c_common_parse_file()
???:0
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Compiler returned: 1
