[Bug c++/119844] Incomplete types are displayed after the import module

[printfne at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119844

--- Comment #1 from printfne at gmail dot com ---
☁  demo gcc15 -v       
使用内建 specs。
COLLECT_GCC=/home/yongheng/gcc15/bin/gcc
COLLECT_LTO_WRAPPER=/home/yongheng/gcc15/libexec/gcc/x86_64-pc-linux-gnu/15.0.1/lto-wrapper
目标：x86_64-pc-linux-gnu
配置为：../configure --enable-checking=release -enable-languages=c,c++
-disable-multilib --prefix=/home/yongheng/gcc15
线程模型：posix
支持的 LTO 压缩算法：zlib zstd
gcc 版本 15.0.1 20250305 (experimental) (GCC)