https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88324
Bug ID: 88324
Summary: segfault with constexpr lambda in template arguments
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: amonakov at gcc dot gnu.org
Target Milestone: ---
With -std=c++17 GCC segfaults on
template<int=[]()constexpr{return 42;}()>
int f()
{
return 0;
}
template int f();
Clang accepts with -fsyntax-only, segfaults trying to mangle. MSVC accepts. GCC
produces
<source>: In lambda function:
<source>:1:35: error: invalid use of 'auto'
1 | template<int=[]()constexpr{return 42;}()>
| ^~
<source>:1:35: error: could not convert '42' from 'int' to 'auto'
<source>: At global scope:
<source>:1:14: error: use of '<lambda()>' before deduction of 'auto'
1 | template<int=[]()constexpr{return 42;}()>
| ^~~~~~~~~~~~~~~~~~~~~~~~~
<source>: In static member function 'static auto<lambda()>::_FUN()':
<source>:1:14: error: invalid use of 'auto'
<source>: At global scope:
<source>:1:40: internal compiler error: Segmentation fault
