https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109789
--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #7)
> It also seems to depend on array-to-pointer decay from float[nframes] to
> float* across the function boundary, because if the loop using the size_t
> index is moved into the same function as the array initialization, the
> analyzer doesn't complain.
Ah no, this still complains without a separate function:
void sink(int);
void export_audio(int nframes, int init, int count) {
do {
int tmp_l[nframes];
for (int i = 0; i < nframes; i++)
tmp_l[i] = init;
unsigned size = nframes;
sink(tmp_l[size - 1]);
} while (--count);
}
a.c: In function ‘export_audio’:
a.c:9:5: error: use of uninitialized value ‘*tmp_l[<unknown>]’ [CWE-457]
[-Werror=analyzer-use-of-uninitialized-value]
9 | sink(tmp_l[size - 1]);
| ^~~~~~~~~~~~~~~~~~~~~
‘export_audio’: events 1-4
|
| 5 | int tmp_l[nframes];
| | ^~~~~
| | |
| | (1) region created on stack here
| 6 | for (int i = 0; i < nframes; i++)
| | ~~~~~~~~~~~
| | |
| | (2) following ‘false’ branch (when ‘i >=
nframes’)...
| 7 | tmp_l[i] = init;
| 8 | unsigned size = nframes;
| | ~~~~
| | |
| | (3) ...to here
| 9 | sink(tmp_l[size - 1]);
| | ~~~~~~~~~~~~~~~~~~~~~
| | |
| | (4) use of uninitialized value ‘*tmp_l[<unknown>]’ here
|
cc1: some warnings being treated as errors
