Tested x86_64-linux, built on avr. Pushed to trunk.
I might backport this to gcc-12 too, although realistically I doubt
anybody is going to try to use the filesystem library on avr anyway, so
it doesn't matter.
-- >8 --
Because avr-libc <errno.h> defines most error numbers with duplicate
values it's not sufficient to check #ifdef ENOTSUP when deciding which
std::errc constant to use for the filesystem library's __unsupported()
helper. Add a special case for AVR to always use the ENOSYS value.
libstdc++-v3/ChangeLog:
* src/filesystem/ops-common.h [AVR] (__unsupported): Always use
errc::function_not_supported instead of errc::not_supported.
---
libstdc++-v3/src/filesystem/ops-common.h | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/libstdc++-v3/src/filesystem/ops-common.h
b/libstdc++-v3/src/filesystem/ops-common.h
index 02c75be09d2..abbfca43e5c 100644
--- a/libstdc++-v3/src/filesystem/ops-common.h
+++ b/libstdc++-v3/src/filesystem/ops-common.h
@@ -84,7 +84,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
inline error_code
__unsupported() noexcept
{
-#if defined ENOTSUP
+#if defined __AVR__
+ // avr-libc defines ENOTSUP and EOPNOTSUPP but with nonsense values.
+ // ENOSYS is defined though, so use an error_code corresponding to that.
+ // This contradicts the comment above, but we don't have much choice.
+ return std::make_error_code(std::errc::function_not_supported);
+#elif defined ENOTSUP
return std::make_error_code(std::errc::not_supported);
#elif defined EOPNOTSUPP
// This is supposed to be for socket operations
--
2.39.1
