https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94978
Bug ID: 94978
Summary: [8/9/10/11 Regression] Bogus warning "Array reference
at (1) out of bounds in loop beginning at (2)"
Product: gcc
Version: 8.4.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: foreese at gcc dot gnu.org
Target Milestone: ---
Created attachment 48472
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48472&action=edit
Testcase which exhibits the regression
The following issues a bogus warning which cannot be disabled except with -w.
The warning is not present in 7.x or earlier. Tried with 8.4.1, 9.3.1, 10 and
11.x (current trunk). Attached is a simple test case, which builds Pascal's
triangle of order 8 and exhibits the regression.
$ gfortran pascal.f03
pascal.f03:13:25:
10 | do i = 0, 8
| 2
......
13 | pascal(i,j) = pascal(i-1,j) + pascal(i-1,j-1)
| 1
Warning: Array reference at (1) out of bounds (-1 < 0) in loop beginning at (2)
pascal.f03:13:41:
10 | do i = 0, 8
| 2
......
13 | pascal(i,j) = pascal(i-1,j) + pascal(i-1,j-1)
| 1
Warning: Array reference at (1) out of bounds (-1 < 0) in loop beginning at (2)
