https://gcc.gnu.org/g:92b38ec84f2990d217f036dc6c5a32cde5ecfb93
commit r14-9879-g92b38ec84f2990d217f036dc6c5a32cde5ecfb93
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Mon Apr 8 17:37:32 2024 +0100
libstdc++: Fix build for targets without FP std::from_chars [PR114633]
If the faster std::from_chars is not supported for floating-point types
then just extract the value from the stream using operator>>.
This fixes a build error for targets where __cpp_lib_to_chars is not
defined.
libstdc++-v3/ChangeLog:
PR libstdc++/114633
* include/bits/chrono_io.h (_Parser::operator()) <'S'>: Use
stream extraction if std::from_chars is not available.
Diff:
---
libstdc++-v3/include/bits/chrono_io.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/libstdc++-v3/include/bits/chrono_io.h
b/libstdc++-v3/include/bits/chrono_io.h
index b9eb3d2be53..3b34992b42a 100644
--- a/libstdc++-v3/include/bits/chrono_io.h
+++ b/libstdc++-v3/include/bits/chrono_io.h
@@ -3685,6 +3685,7 @@ namespace __detail
if (!__is_failed(__err)) [[likely]]
{
long double __val{};
+#if __cpp_lib_to_chars
string __str = std::move(__buf).str();
auto __first = __str.data();
auto __last = __first + __str.size();
@@ -3694,6 +3695,9 @@ namespace __detail
if ((bool)ec || ptr != __last) [[unlikely]]
__err |= ios_base::failbit;
else
+#else
+ if (__buf >> __val)
+#endif
{
duration<long double> __fs(__val);
if constexpr (__is_floating)
