https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77650
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> --- Thanks for the background. It's unfortunate but I hope the Glibc code can be accommodated without preventing GCC from detecting the same problem in user code (and rejecting it with a hard error). One approach might be to base the kind of the diagnostic (pedantic warning vs hard error) on whether the code appears in a system header. Longer term, Glibc could be changed to use a zero-length array instead of a flexible array member so that the GCC workaround could eventually be removed. Another, perhaps more appropriate, approach might be to add a new warning under -Wall and use it to diagnose this constraint violation. The warning would be suppressed for system headers, allowing GCC to silently accept the Glibc code.
