https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95330
Bug ID: 95330
Summary: Unneeded -Wmissing-braces warning when initialising
std::array
Product: gcc
Version: 10.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: szotsaki at gmail dot com
Target Milestone: ---
Example code:
#include <array>
int main() {
const volatile std::array<int, 3> a = {1, 2, 3};
return 0;
}
Compile with "-std=c++17 -Wmissing-braces" and the following warning is shown:
t.cpp: In function ‘int main()’:
t.cpp:3:48: warning: missing braces around initializer for
‘std::__array_traits<int, 3>::_Type’ {aka ‘int [3]’} [-Wmissing-braces]
3 | const volatile std::array<int, 3> a = {1, 2, 3};
| ^
The same message occurs when you initialise in either way:
* std::array<int, 3> a = {1, 2, 3};
* std::array<int, 3> a{1, 2, 3};
According to cppreference.com [1] it's not necessary to use the second level of
braces since CWG 1270 [2] from C++11 on.
clang does not warn for the same line of code.
[1]: https://en.cppreference.com/w/cpp/container/array
[2]: http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1270
