| Submitter | Thomas Koenig |
|---|---|
| Date | March 31, 2011, 8:28 p.m. |
| Message ID | <4D94E40A.2060306@netcologne.de> |
| Download | mbox | patch |
| Permalink | /patch/89126/ |
| State | New |
| Headers | show |
Comments
On 03/31/2011 01:28 PM, Thomas Koenig wrote: > Hello world, > > the attached patch fixes a 4.7 regression, PR 48352, where a function > elimination in the expressions for a DO loop caused an ICE. The ICE was caused > by interaction of the expression walker with insertion of a statement for a DO > loop. > > Many thanks to Joost for finding the bug and reducing the test case. > > To fix the regression, I have disabled this particular optimization for > expressions within the loop control. > > I'd like to overhaul the way that statements are inserted during front end > optimization, later. This is needed for functions returning arrays with bounds > not known at compile-time anyway. > > Regression-tested. OK for trunk? > OK. Do you plan to open a second PR for this TODO? Thanks for patch, Jerry
Hi Jerry, >> Regression-tested. OK for trunk? >> > OK. Do you plan to open a second PR for this TODO? Sending fortran/ChangeLog Sending fortran/frontend-passes.c Sending testsuite/ChangeLog Adding testsuite/gfortran.dg/function_optimize_3.f90 Transmitting file data .... Committed revision 171849. I have opened PR 48405 to track the issue. Thanks for the review! Thomas
Patch
Index: frontend-passes.c =================================================================== --- frontend-passes.c (Revision 171793) +++ frontend-passes.c (Arbeitskopie) @@ -137,6 +137,13 @@ static int cfe_register_funcs (gfc_expr **e, int *walk_subtrees ATTRIBUTE_UNUSED, void *data ATTRIBUTE_UNUSED) { + + /* FIXME - there is a bug in the insertion code for DO loops. Bail + out here. */ + + if ((*current_code)->op == EXEC_DO) + return 0; + if ((*e)->expr_type != EXPR_FUNCTION) return 0;
Hello world, the attached patch fixes a 4.7 regression, PR 48352, where a function elimination in the expressions for a DO loop caused an ICE. The ICE was caused by interaction of the expression walker with insertion of a statement for a DO loop. Many thanks to Joost for finding the bug and reducing the test case. To fix the regression, I have disabled this particular optimization for expressions within the loop control. I'd like to overhaul the way that statements are inserted during front end optimization, later. This is needed for functions returning arrays with bounds not known at compile-time anyway. Regression-tested. OK for trunk? Thomas 2011-03-31 Thomas Koenig <tkoenig@gcc.gnu.org> PR fortran/48352 * frontend-passes (cfe_register_funcs): Don't register functions if they appear as iterators in DO loops. 2011-03-31 Thomas Koenig <tkoenig@gcc.gnu.org> PR fortran/48352 * gfortran.dg/function_optimize_3.f90: New test. ! { dg-do compile } ! { dg-options "-O" } ! PR 48352 - variable elimination in a DO loop caused segfaults. ! Test case contributed by Joost VandeVondele program main INTEGER, DIMENSION(:), POINTER :: a DO I=1,MIN(SIZE(a),SIZE(a)) ENDDO END program main