https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77369
Bug ID: 77369
Summary: incorrect noexcept specification deduction
Product: gcc
Version: 6.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: aaron.ballman+gcc at gmail dot com
Target Milestone: ---
The following code produces "false, false" with Clang 3.8.0 and MSVC 2015, but
"true, true" with GCC 6.1.0 (and EDG).
#include <iostream>
template <typename Func>
int some_function(int param, Func fn) noexcept(noexcept(fn(param))) {
return fn(param);
}
int noexcept_fn(int) noexcept(true) { return 0; }
int not_noexcept_fn(int) noexcept(false) { return 0; }
int main() {
std::cout << std::boolalpha <<
noexcept(some_function(0, noexcept_fn)) << ", " <<
noexcept(some_function(0, not_noexcept_fn)) << std::endl;
}
This is dangerous because it means that if not_noexcept_fn() throws (as it is
allowed to do per its exception specification) when called from
some_function(), it results in std::terminate() being called due to
some_function() having the wrong exception specification.
This happens with -std=c++14, where exception specifications are not considered
part of the type system.
