[cfe-dev] Recent minor C regression (maybe)

[Bruce Stephens]

The following dubious (IMHO) code no longer compiles, though it does in
other popular compilers.

static void a(void);
extern void a();
static void a(void) {}

(In this specific case the code is partly generated: the extern
declaration is generated and the static ones are hand generated.)

I'm guessing this is caused by reverting the reversion of r178663 (it
touches what looks like the right bit of code and it's dated April 3, so
the timing's about right), but I haven't checked.

(Not sure whether the code should be legal. I'd guess we don't have the
only instance of this kind of thing.)