Message ID | CAE4aFAkArCKp5jyuToj+NFw=-PwZ481LUe6dp7NG_MjAqKCrPA@mail.gmail.com |
---|---|
State | New |
Headers | show |
On Wed, Oct 05, 2016 at 04:40:50PM -0400, Fritz Reese wrote: > When union type symbols are compared and they contain maps containing > characters with different lengths, their type symbols should have > different backend declarations otherwise the gimple tree explodes. > Strangely enough the gimple checker only explodes with '-g' enabled > and certain other specific conditions, however the problem seems > clear. See the attached testcase for an example, and the attached > patch for a fix. > > RFC: My only concern is that this patch would technically also change > the way components are compared between derived types and class types, > not just union/map types. However from what I can tell if two derived > types are declared with character components of different lengths then > the two types should have distinct backend declarations anyway. If > anyone can think of any issues this patch might cause with derived > types/class types then I'd be okay guarding the new if statement to > only run for union/structure types. But with all my tests it doesn't > seem to result in any concrete differences. > > The patch does pass all regression tests on x86_64-redhat-linux. I > will give it a couple days for the RFC before committing. > > --- > Fritz Reese > > 2016-10-05 Fritz Reese <fritzoreese@gmail.com> > > Fix ICE due to map typespecs with different sized charlens being copied. > > * gcc/fortran/interface.c (compare_components): Check charlens. > > * gcc/testsuite/gfortran.dg/dec_union_11.f90: New testcase. > Patch looks ok to me.
diff --git a/gcc/fortran/interface.c b/gcc/fortran/interface.c index e7f1878..17f544e 100644 --- a/gcc/fortran/interface.c +++ b/gcc/fortran/interface.c @@ -495,6 +495,17 @@ compare_components (gfc_component *cmp1, gfc_component *cmp2, if (cmp1->attr.dimension && gfc_compare_array_spec (cmp1->as, cmp2->as) == 0) return 0; + if (cmp1->ts.type == BT_CHARACTER && cmp2->ts.type == BT_CHARACTER) + { + gfc_charlen *l1 = cmp1->ts.u.cl; + gfc_charlen *l2 = cmp2->ts.u.cl; + if (l1 && l2 && l1->length && l2->length + && l1->length->expr_type == EXPR_CONSTANT + && l2->length->expr_type == EXPR_CONSTANT + && gfc_dep_compare_expr (l1->length, l2->length) != 0) + return 0; + } + /* Make sure that link lists do not put this function into an endless recursive loop! */ if (!(cmp1->ts.type == BT_DERIVED && derived1 == cmp1->ts.u.derived) diff --git a/gcc/testsuite/gfortran.dg/dec_union_11.f90 b/gcc/testsuite/gfortran.dg/dec_union_11.f90 new file mode 100644 index 0000000..3ff4b49 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/dec_union_11.f90 @@ -0,0 +1,63 @@ +! { dg-do compile } +! { dg-options "-g -fdec-structure" } +! +! Test a regression where typespecs of unions containing character buffers of +! different lengths where copied, resulting in a bad gimple tree state. +! + +subroutine sub2 (otherbuf) + integer, parameter :: L_bbuf = 65536 + integer, parameter :: L_bbuf2 = 24 + + structure /buffer2/ + union + map + character(L_bbuf2) sbuf + end map + end union + end structure + structure /buffer/ + union + map + character(L_bbuf) sbuf + end map + end union + end structure + + record /buffer/ buf1 + record /buffer2/ buf2 + common /c/ buf1, buf2 + + record /buffer2/ otherbuf +end subroutine + +subroutine sub() + integer, parameter :: L_bbuf = 65536 + integer, parameter :: L_bbuf2 = 24 + + structure /buffer2/ + union + map + character(L_bbuf2) sbuf + end map + end union + end structure + structure /buffer/ + union + map + character(L_bbuf) sbuf + end map + end union + end structure + + record /buffer/ buf1 + record /buffer2/ buf2 + common /c/ buf1, buf2 + + call sub2 (buf1) ! { dg-warning "Type mismatch" } + return +end subroutine + +call sub() + +end