https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108013
LIU Hao <lh_mouse at 126 dot com> changed:
What |Removed |Added
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CC| |lh_mouse at 126 dot com
--- Comment #2 from LIU Hao <lh_mouse at 126 dot com> ---
Clang doesn't warn about it.
```
extern "C" int a = 1; // GCC warns; Clang doesn't.
extern int b = 1; // Both warn.
extern const int c = 1; // Neither warns; `extern` is required to denote
// external linkage.
``
