| Summary: | [4.3 Regression] Wrong alias info for array access | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Richard Biener <rguenth> |
| Component: | tree-optimization | Assignee: | Not yet assigned to anyone <unassigned> |
| Status: | RESOLVED DUPLICATE | ||
| Severity: | normal | CC: | fang, gcc-bugs, rguenth, sabre |
| Priority: | P3 | Keywords: | alias, wrong-code |
| Version: | 4.3.2 | ||
| Target Milestone: | 4.3.3 | ||
| Host: | Target: | ||
| Build: | Known to work: | ||
| Known to fail: | Last reconfirmed: | ||
Actually this is a dup of PR37868. The points-to results for the access are wrong: D.1577_7 = &mat + D.1576_6; # VUSE <SFT.18_14> D.1578_8 = (*D.1577_7)[0]; from the constraints D.1577_7 = &mat D.1577_7 = D.1576_6 (which are wrong) we compute D.1577_7 = { mat } but correct would be { mat mat.32 } with the fix for PR37868 we immediately say D.1577_7 = { ANYTHING } and this becomes a pessimization for field-sensitive points-to analysis. See PR38049 for this. *** This bug has been marked as a duplicate of 37868 *** |
extern void abort(void); int foo () { int mat[2][1]; int (*a)[1] = mat; int det = 0; int i; mat[0][0] = 1; mat[1][0] = 2; for (i = 0; i < 2; ++i) det += a[i][0]; return det; } int main() { if (foo () != 3) abort (); return 0; }