https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114863
Bug ID: 114863
Summary: std::format applying grouping to nan's and inf's
Product: gcc
Version: 13.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: lcarreon at bigpond dot net.au
Target Milestone: ---
The following code:
#include <locale>
#include <limits>
#include <iostream>
#include <format>
int main()
{
std::locale::global(std::locale{"en_AU.utf8"});
double values[] =
{
std::numeric_limits<double>::quiet_NaN(),
-std::numeric_limits<double>::quiet_NaN(),
std::numeric_limits<double>::signaling_NaN(),
-std::numeric_limits<double>::signaling_NaN(),
std::numeric_limits<double>::infinity(),
-std::numeric_limits<double>::infinity()
};
for (const auto& value : values)
{
std::cout << std::format("{0:Le} {0:Lf} {0:Lg}", value) << std::endl;
}
return 0;
}
Generates the following output:
nan nan nan
-,nan -,nan -,nan
nan nan nan
-,nan -,nan -,nan
inf inf inf
-,inf -,inf -,inf
Which in my opinion is incorrect because it applied thousands separator
grouping. Grouping should only be applied to finite values displayed in fixed
format.
