[Bug c++/92494] New: ICE on function templates with placeholder return type decltype([]{}) and return type doesn't match

[boostcpp at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92494

            Bug ID: 92494
           Summary: ICE on function templates with placeholder return type
                    decltype([]{})  and return type doesn't match
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: boostcpp at gmail dot com
  Target Milestone: ---

Following code produce the ICE on GCC 9 and the GCC 10 latest HEAD:

template < typename T >
decltype([]{}) f( )
{ return 0 ; }

int main ()
{ f<void>() ; }

https://wandbox.org/permlink/Cto4TbyBw0U3ywkB


Expected behaviour:

main.cpp: In function ‘<lambda()> f()’:
main.cpp:3:10: error: could not convert ‘0’ from ‘int’ to ‘<lambda()>’

Actual behaviour:

g++: internal compiler error: Segmentation fault signal terminated program
cc1plus
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