On Mon, Sep 07, 2026 at 09:59:04PM +0800, Jakit Liang wrote:
> Tested on x86_64-linux-gnu with g++ and clangd 18/19.
>
> Signed-off-by: Jakit Liang <[email protected]>
> ---
> libstdc++-v3/include/bits/c++config | 2 +-
> libstdc++-v3/include/std/format | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/libstdc++-v3/include/bits/c++config
> b/libstdc++-v3/include/bits/c++config
> index 60456a48681..072da451df8 100644
> --- a/libstdc++-v3/include/bits/c++config
> +++ b/libstdc++-v3/include/bits/c++config
> @@ -892,7 +892,7 @@ namespace std
> #if defined __cplusplus && defined __BFLT16_DIG__
> namespace __gnu_cxx
> {
> - typedef __decltype(0.0bf16) __bfloat16_t;
> + typedef __bf16 __bfloat16_t;
This is incorrect.
__bf16 is the type of 0.0bf16 literals only on some targets, not all.
You haven't explained why is __BFLT16_DIG__ defined when compiling with
clangd, it shouldn't be when it doesn't support bfloat16_t properly.
Are you defining it by hand on the command line or in some user header
or main source before including the libstdc++ headers?
Jakub
