This adds support for clobbering of variables passed by reference, when the reference is forwarded to a subroutine as actual argument whose associated dummy has the INTENT(OUT) attribute. This was explicitly disabled and enabling it seems to work, as demonstrated by the new testcase.
PR fortran/41453 gcc/fortran/ChangeLog: * trans-expr.cc (gfc_conv_procedure_call): Remove condition disabling clobber generation for dummy variables. Remove obsolete comment. gcc/testsuite/ChangeLog: * gfortran.dg/intent_optimize_6.f90: New test. --- gcc/fortran/trans-expr.cc | 4 --- .../gfortran.dg/intent_optimize_6.f90 | 34 +++++++++++++++++++ 2 files changed, 34 insertions(+), 4 deletions(-) create mode 100644 gcc/testsuite/gfortran.dg/intent_optimize_6.f90 diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc index 2301724729f..9b2832bdb26 100644 --- a/gcc/fortran/trans-expr.cc +++ b/gcc/fortran/trans-expr.cc @@ -6527,8 +6527,6 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym, && !e->symtree->n.sym->attr.dimension && !e->symtree->n.sym->attr.pointer && !e->symtree->n.sym->attr.allocatable - /* See PR 41453. */ - && !e->symtree->n.sym->attr.dummy /* FIXME - PR 87395 and PR 41453 */ && e->symtree->n.sym->attr.save == SAVE_NONE && !e->symtree->n.sym->attr.associate_var @@ -6538,8 +6536,6 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym, && !sym->attr.elemental) { tree var; - /* FIXME: This fails if var is passed by reference, see PR - 41453. */ var = build_fold_indirect_ref_loc (input_location, parmse.expr); tree clobber = build_clobber (TREE_TYPE (var)); diff --git a/gcc/testsuite/gfortran.dg/intent_optimize_6.f90 b/gcc/testsuite/gfortran.dg/intent_optimize_6.f90 new file mode 100644 index 00000000000..72fec3db583 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/intent_optimize_6.f90 @@ -0,0 +1,34 @@ +! { dg-do run } +! { dg-additional-options "-fno-inline -fno-ipa-modref -fdump-tree-optimized -fdump-tree-original" } +! +! PR fortran/41453 +! Check that the INTENT(OUT) attribute causes one clobber to be emitted in +! the caller before each call to FOO in the *.original dump, and the +! initialization constant to be optimized away in the *.optimized dump, +! in the case of an argument passed by reference to the caller. + +module x +implicit none +contains + subroutine foo(a) + integer(kind=4), intent(out) :: a + a = 42 + end subroutine foo + subroutine bar(b) + integer(kind=4) :: b + b = 123456789 + call foo(b) + end subroutine bar +end module x + +program main + use x + implicit none + integer(kind=4) :: c + call bar(c) + if (c /= 42) stop 1 +end program main + +! { dg-final { scan-tree-dump-times "CLOBBER" 1 "original" } } +! { dg-final { scan-tree-dump "\\*\\\(integer\\\(kind=4\\\) \\*\\\) b = {CLOBBER};" "original" } } +! { dg-final { scan-tree-dump-not "123456789" "optimized" { target __OPTIMIZE__ } } } -- 2.35.1