Sorry in advance if this is a silly question; my knowledge of Fortran
is next to nothing, I'm afraid.
PR analyzer/107210 reports an ICE in -fanalyzer on this reproducer:
! { dg-additional-options "-O1" }
subroutine check_int (j)
INTEGER(4) :: i, ia(5), ib(5,4), ip, ipa(:)
target :: ib
POINTER :: ip, ipa
logical :: l(5)
l = (/ sizeof(i) == 4, sizeof(ia) == 20, sizeof(ib) == 80, &
sizeof(ip) == 4, sizeof(ipa) == 8 /) ! { dg-warning "use of
uninitialized value" }
if (any(.not.l)) STOP 4
end subroutine check_int
The fix for the ICE is trivial (a missing check that tree_fits_uhwi_p),
but after the fix, I see these warnings from the analyzer:
10 | sizeof(ip) == 4, sizeof(ipa) == 8 /)
| ^
Warning: use of uninitialized value ‘ipa.dim[0].ubound’ [CWE-457]
[-Wanalyzer-use-of-uninitialized-value]
‘check_int’: events 1-3
|
| 4 | INTEGER(4) :: i, ia(5), ib(5,4), ip, ipa(:)
| | ^
| | |
| | (1) region created on
stack here
| | (2) capacity: 8 bytes
|......
| 10 | sizeof(ip) == 4, sizeof(ipa) == 8 /)
| | ~
| | |
| | (3) use of uninitialized
value ‘ipa.dim[0].ubound’ here
|
../../src/gcc/testsuite/gfortran.dg/analyzer/pr107210.f90:10:43:
10 | sizeof(ip) == 4, sizeof(ipa) == 8 /)
| ^
Warning: use of uninitialized value ‘ipa.dim[0].lbound’ [CWE-457]
[-Wanalyzer-use-of-uninitialized-value]
‘check_int’: events 1-3
|
| 4 | INTEGER(4) :: i, ia(5), ib(5,4), ip, ipa(:)
| | ^
| | |
| | (1) region created on
stack here
| | (2) capacity: 8 bytes
|......
| 10 | sizeof(ip) == 4, sizeof(ipa) == 8 /)
| | ~
| | |
| | (3) use of uninitialized
value ‘ipa.dim[0].lbound’ here
|
The gimple in question is:
__attribute__((fn spec (". w ")))
void check_int (integer(kind=4) & restrict j)
{
integer(kind=8) ipa$dim$0$lbound;
integer(kind=8) ipa$dim$0$ubound;
logical(kind=4) A.1[5];
logical(kind=4) l[5];
integer(kind=8) _1;
logical(kind=4) _3;
logical(kind=4) _4;
integer(kind=8) _5;
logical(kind=4) _6;
integer(kind=8) S.5_7;
logical(kind=4) test.6_8;
integer(kind=8) S.7_9;
integer(kind=8) S.5_16;
integer(kind=8) S.7_18;
<bb 2> [local count: 178992760]:
MEM <uint128_t> [(c_char * {ref-all})&A.1] = 0x1000000010000000100000001;
_1 = ipa$dim$0$ubound_2(D) - ipa$dim$0$lbound_12(D);
_3 = _1 == 1;
MEM[(logical(kind=4) *)&A.1 + 16B] = _3;
[...snip...]
where the analyzer is complaining about this gimple statement:
_1 = ipa$dim$0$ubound_2(D) - ipa$dim$0$lbound_12(D);
where both:
ipa$dim$0$ubound_2(D)
and:
ipa$dim$0$lbound_12(D)
are considered by it to be uninitialized.
Is the analyzer correct here, or is there an aspect of Fortan and/or
gimple that I'm missing?
Thanks
Dave
