[Bug c++/89513] constexpr functions with function try block shouldn't be accepted at least with -pedantic in -std=c++{11,14,17} modes

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89513

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2019-02-26
                 CC|                            |msebor at gcc dot gnu.org
             Blocks|                            |55004
     Ever confirmed|0                           |1

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
Confirmed.  Clang 7 prints:

$ clang++ -S -Wall pr89513.C
pr89513.C:2:1: error: function try block not allowed in constexpr function
try {
^
pr89513.C:9:3: error: statement not allowed in constexpr function
  try { return true; } catch (...) {}
  ^
2 errors generated.


The latest Clang with -Wall:

pr89513.C:3:1: warning: function try block in constexpr function is a C++2a
extension [-Wc++2a-extensions]
try {
^
pr89513.C:6:1: warning: control may reach end of non-void function
[-Wreturn-type]
}
^
pr89513.C:10:3: warning: use of this statement in a constexpr function is a
C++2a extension [-Wc++2a-extensions]
  try { return true; } catch (...) {}
  ^
pr89513.C:14:16: warning: unused variable 'a' [-Wunused-const-variable]
constexpr auto a = foo ();
               ^
pr89513.C:15:16: warning: unused variable 'b' [-Wunused-const-variable]
constexpr auto b = bar ();
               ^
5 warnings generated.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55004
[Bug 55004] [meta-bug] constexpr issues