https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107952
--- Comment #5 from Siddhesh Poyarekar <siddhesh at gcc dot gnu.org> ---
(In reply to rguent...@suse.de from comment #4)
> Does it allow the nesting when nested in a union?
data[] cannot be nested directly in a union (i.e. union { char d; char data[];
} is invalid) but something like below is allowed, again as a gcc extension,
not by the standard. The standard AFAICT doesn't allow anything other than the
flex array directly at the end of the top level struct.
typedef struct {
unsigned pad;
union {
struct {char d; char data[];} f1;
struct {char d; char data[];} f2;
} flex;
} S2;
In fact this is the use case that led me into this rabbithole.
